EXPERIMENTS IN TEACHING CHILDREN COMPUTER

EXPERIMENTS IN TEACHING

CHILDREN COMPUTER PROGRAMMING

by

A. B. Cannara

TECHNICAL REPORT NO. 271May, 1976

PSYCHOLOGY AND EDUCATION SERIES

Reproduction in Wbole or in Part Is Permitted

for Any Purpose of the United States Government

INSTITUTE FOR MATHEMATICAL STUDIES IN THE SOCIAL SCIENCES

STANFORD UNIVERSITY

STANFORD, CALIFORNIA 94305

Foreword

This dissertation is actually an extension and continuation of an earlier

technical report (Weyer & Cannara, 1975), which herein is called "report-I".

Report-l should (but need not) be read in conjunction with this document.

As a matter of notation, all phrases in the text that are not in English,

but in the computer languages being discussed, are surrounded by single quotes

('), unless their context is otherwise obvious. As a matter of taste, which

rejects the "arrogance of the acronym", names of programming languages and

other proper nouns, excepting trade or institutional names, receive their due

. quota of capitals--one.

Several references are made to articles in a few common periodicals, not

necessarily because the articles are uniquely relevant, but because the

periodicals are easily found and their editors traditionally strive for clarity as

well as accuracy.

III

Acknowledgements

This work was supported by National Science Foundation Grant NSF-GJ

443X. I thank Patrick Suppes for his helpful advice and for use of the IMSSS

computing facilities. I am further indebted to my student volunteers. They

remain anonymous, but they were the most important people in the experiments.

Steve Weyer deserves thanks for his imaginative work on the original Logo

curriculum, for maintaining the Logo interpreter and for developing the Sailogo

graphics system. I also thank Adele Goldberg for her editorial assistance.

iv

Table of Contents

Forward..............................•.•....................................................•............................... iii

Acknowledgements........•.................................................•.......................................• iv

Index to Tables.................••......................•..............................••.....................•.•......vi

Index to Figures vii

Chapters

1 Introduction :...................................... 1

2 Programming Facilities 10

Languages 10

Peripheral Devices 23

3 Students, Tutoring and Curricula 30

4 Data Acquisition and Analysis : 55

5 Results 63

References 113

Appendices

1 Spm 119

2 Aptitude-Testing Details 125

3 Sample Curricula 135

4 Student Programs 163

v

Index of Tables

I. Some Fundamental Programming Concepts..................................... 7

II. Simper Machine Operations 14

III. Simper Interpreter Commands 15

IV. Some Logo Primitives 18

V. Logo's Procedure Editing and Debugging Commands 19

VI. Logo's File-manipulation Commands 20

VII. Simper/Logo Line-editing Commands 21

VIII. IMSSS Logo Turtle-Graphics Commands 26

IX IMSSS Logo Animation Commands 27

X Experimental Groups 31

XI Categorization of Observed Student Errors and Misconceptions.Il1

vi

Index of Figures

1. Simper and Logo Sample Dialogues...............................•..............•....... 11

2. Structure of Simper's Simulated Machine 13

3. Displaying a Simper Program's Activi ty 16

4. Tracing a Logo Procedure's Activity 22

5. Programming System Structure 24

6. Successive Frames from a Logo-Animation "Movie 29

7a. Some Information Characterizing the 1973 Students........................• 33

7b. Some Information Characterizing the 1974 Students 34

8. Some "Wrong" Answers from the 1973 Preliminary Test 38

9. Some Novel Answers from the Preliminary Tests..•.........•.................39

lOa. Student Ranking on the 1973 Preliminary Test .42

lOb. Student Ranking on the 1974 Preliminary Test 43

11. A Simple Quantitative Analysis of Protocols 61

12a. The 1973 Students' Preferences 64

12b. Some 1974 Students' Opinions 65

13. Some 1974 Students' Preliminary Feelings 67

14a. Breakdown of the 1973-Students' Programming Time 69

14b. Breakdown of the 1974-Students' Programming Time 70

vii

15a. 1973 Simper Students' Performance Versus Pretest Rank 72

15b. 1973 Logo Students' Performance Versus Pretest Rank 73

16. 1974 Students' Performance Versus Pretest Rank 74

17. Timing of 1974 Students' Mastery of Simper-related Concepts 86

18. Timing of 1974 Students' Mastery of Logo-related Concepts 95

viii

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1. Introduction

Herein are discussed in detail two experiments done at the Institute for

Mathematical Studies in the Social Sciences (IMSSS) at Stanford during the

summer of 1973 and the spring of 1974. Previously, Cannara and Weyer

(1974a), and Weyer and Cannara (1975), have described the 1973 experiment; it

will be referred to as the "first" experiment. The 1975 document will be

called "report-I".

The experiments attempted to study children, who had never used a

~~",puter before, learning: (a) concepts relevant to computer programming, and

(b) modern programming languages. The languages and other programming

facilities used (e.g., graphics) have been discussed definitively in report-I; this

thesis will simply outline their features and concentrate on observations of the

childrens' learning-processes and the implications of both experiments in terms

of programming-language and curriculum design, and tutoring technique.

Why observe children learning computer-programming? Programming would

seem to be a decidedly adult task for young people who haven't yet completed

their basic schooling. A partial, motivational answer follows immediately; the

remainder of this thesis may be viewed as an attempt to complete that an'swer.

Three main streams of thought converge on the study of children learning

to use a computer. First, is the view that a computer is in fact a tool for

thinking, which implies that it might be applied fruitfully at every educational

level (e.g., Brown & Rubinstein, 1973; Dwyer, 1972; Feurzeig, Papert, Bloom,

Grant & Solomon, 1969; Kay, 1972[b]; Papert, 1970). In particular, the

computer can be used to stimulate the activity Papert has referred to as

"thinking about thinking". Second, is the desire of some educators to study the

thinking processes of people solving problems (e.g., Bloom & Broder, 1950;

Piaget, 1970; Polya, 1957), which leads directly to studies in perhaps the most

general problem-solving realm: computer programming. Third, is a synthesis of

human problem-solving and computer-as-tool, flamboyantly named "artificial-

intelligence research", which aims to formalize problem-solving procedures (e.g.,

Feigenbaum & Feldman, 1963; Minsky, 1968; Newell & Simon, 1972; Nilson,

1971; Winograd, 1971). Sometimes, artificial-intelligence products can better

our understanding of ourselves and/or provide useful educational strategies (e.g.,

Brown & Burton, 1974; Goldberg, 1973).

We should not be surprised to find children and computers where those

three streams intersect. The educational linkage of computer programming with

thinking is expressed by the idea of a "mathematical laboratory", in which a

program creates a constructively interactive, and so perhaps more interesting

environment for learning. Unlike most traditional realizations of computer-

assisted-instruction (Cai), the laboratory is designed to "understand", at a

meaningful level, the domain of interest. 1 Unlike most classroom lectures, such

a laboratory can give substance to the material and exploratory freedom to its

users. The user's interaction with a mathematical laboratory is mediated by a

formal (as opposed to natural) language, whose semantics access the constructive

abilities of the laboratory and whose syntax is simply a perhaps novel set of

conventions. A computer and a programming language together constitute a

mathematical laboratory of the most general kind, because they are all that are,

needed to construct (simulate) any other laboratory. That is the main

justification for studying programming as a general problem-solving activity. It

is based upon a conjecture of Church's that (freely interpreted) suggests that

any ideas which may be formalized may be studied as a computer ~rogram.2

Formalization of ideas, a fundamental aspect of mathematics, is part and parcel

lSee Ellis (1974) or Oettinger and Marks (1969). for critiques of present educationalcomputer applications; and Smallwood (1962), or Suppes (in Wittrock, 1973), for~istoriCallY typical examples of Cai.

For discussions of Church's thesis, see Manna (1972) or Minsky (l967).

of mathematical laboratories for programming, problem solving and thinking

about thinking.

The production of effective mathematical laboratories is closely and

bidirectionally connected with artificial-intelligence work and human self

understanding. It must grapple with questions beyond the immediate scope of

the laboratories themselves. Effective tutoring techniques, for example, are

educational objectives which must be attained even after one has constructed a

laboratory which "understands" its domain. Thus, applying the computer

educationally, as a tool made available via a laboratory, demands answers to

questions posed in a wide variety of fields (e.g., Brown & Burton, 1974;

Goldberg, 1973).

The theory and practice of computation offer educators some valuable tools:

(a) the formalization of ideas as clustered sequences of instructions, (b) methods

for .modelling real-world processes, and (c) metaphors for understanding machine

and human information-processing. Together, these expose thinking techniques

that PapeEt has termed "powerful ideas". Concepts of programming and

thinking can be taught as natural and inseparable partners, emphasizing

students' scrutiny of their own thinking about the world. And, it is not a new

idea that school-children can and should learn how to program a computer, so

that they too might access its unparalleled power as a tool for thinking. The

computer's natural ability to simulate has responded to the ingenuities of

students (as seen, for example, in the work of Brown and Rubinstein, Dwyer, or

Papert) with the same spectacular generality it has provided to professional

researchers (e.g., Levison, Ward & Webb, 1973; Toomre & Toomre, 1973;

Winograd, 1971).

The foregoing remarks were intended to justify a desire to study

programming as an intellectual activity for children and programming languages

as tools for such activity. As a technological product, the personal computer

will soon be as much a reality, as the personal calculator is today.3 Access to

interactive computation may sOOn become commonplace for vast numbers of

children (and adults), at school or at home. Certainly we should be trying now

to understand how to hone this new tool to maximum usefulness. As a medium

for expressing, manipulating and communicating ideas, the personally accessible

computer may stand well above everything since the printing press.4

Teaching programming is a tutorial endeavor of perhaps the most general

kind. The work to be reported here attempts to characterize some of the

situations that human and mechanical tutors for programming will confront and

must be prepared to resolve. It is relevant to the common ground between

education and artificial intelligence because the construction of computer

programs which can tutor humans with human proficiency is a common goal.

No one has attained that goal yet, because the activities of a good tutor are

tied, irrevocably to humanness of language and knowledge (e.g., Winograd, 1974).

Although the theoretical power of the computer (Le., as conjectured by Church)

may be sufficient to simulate natural intellect, we do not yet understand

ourselves (or other species, e.g., Gardner & Gardner, 1975) well enough to

communica~e even a coarse description of intelligence to any recipient (note the

arguments of Stent, 1975a, 1975b; and his critics). Those who have recognized

the nature of this problem have come .closest to success in carefully limited

contexts (e.g., Brown & Burton, 1974; Carbonell, 1970; Winograd, 1971).

The generality of a programming laboratory and the intimacy of tutoring

combine to produce an interesting research environment in which analysis of

3 See Kay (1975. 1972a. 1972b) or Brand (1974. pp, 64-71) for one view of the nearfuture of computing.4 See Fenichel & Weizenbaum {1971), and Mauchly (1975) for historical pers·pectives onthe computer's development; and Vacroux (1975) for directions that technological eventsare taking now.

errors plays a central role. A programming tutor (human or mechanical) must

be ready to intelligently suggest, accept or comment on an arbitrarily wide

range of student interactions and program syntheses. The details of errors do

more than indicate what a student does not understand, they indicate how the

student views the problem. at hand in terms of his or her own view of the

world.

Extending a suggestion of Papert's, if a student responds to a posed problem.

at all, that response is typically correct by the student's personal analysis. So

the student is surprised to hear "wrong". It is the tutor's responsibility to try

to divine the' reasons for the student's error, perhaps acting as does a detective

eliciting evidence from someone from a foreign land--subsequent interaction is

devoted to laying a common foundation of terms (definitions and relations).

The tutor necessarily learns about the student's world view and is better

prepared to handle future errors and future students. Errors are not "bad",

they provide valuable feedback to be exploited for student benefit.5

However, any tutor (human or mechanical) for teaching something as

general as programming is destined to occasionally fail the student, because it

must occasionally tackle unsolvable (uncomputable) problems.6 In other words,

the tutor must pass judgment on the correctness of a student's program, and we

know that there exists no general procedure for deciding that an arbitrary

program is correct or incorrect. But the range of solvable problems is so broad

that this hard theoretical fact discourages neither researchers nor teachers.

"Proof of program correctness" (Hoare, 1971) and "automatic program synthesis"

--------------------------------------------------------------------------------5 This relates to a basic criticism of most past efforts in Cai: not only have programsbeen designed which fail to understand their own SUbject-matter, they fail to possessmore than trivial error-handling strategies. Results too often have been just transferof programmed-instruction text or film to computer storage. using very little. from thestudent's vantage, of the computer's computational potential. Dwyer has said that Caifails in "reproducing the excitement of masterful teaching". I would add that rarelyaave Cai workers even attempted to capture masterful teaching.

Discussions of the uncomputable (unsolvable or unprovable) appear in Davis (1965),Minsky (1967). Chaitin (1975) and Steen (1975).

(Fenichel, Weizenbaum & Yochelson, 1970) are active topics in computational

research which have clear bearing on future success in constructing competent

computer-based" tutorial systems.

Numerous research projects have taught children particular programming

languages (e.g., Feurzeig and Lukas 1972a; Fischer, 1973; Folk, Statz &

Seidman, 1974; Milner, 1973; Roman, 1972). However, apparently none has

attempted to make explicit the broad range of relevant programming concepts

and their relationship to a student's world of thought. In such terms, many

"projects have pursued hazy, sometimes arbitrary goals that concentrated on

teaching an available language through ad-hoc, problem-solving situations,

without generalizing situations and solution strategies. A study by Folk, et a!.,

(1974) is perhaps the most extensive attempt to specify relationships between

programming concepts and children's thinking processes. But their analysis is

confined to classical statistical models and the concomitant testing of rather

broad hypotheses virtually ignores a wealth of detail.in student protocols.

In contrast, protocols (and tutorial notes) are precisely the data upon which

this work is founded. The primary objective is to understand how children

learn programming concepts (e.g., Table I), with secondary emphasis on the

influences of languages and curricula. With error-analysis as a tool,

student/machine interactions must be exposed in as much detail as possible.

Narrow views, provided for example by conventional test scores, are inadequate

no matter how convenient they may be to obtain and analyze. Quoting Bloom

and Broder on the subject of "objective" tests:

"What is missing is information on the process by whichthe problems are solved. The methods of attack, the steps ofthe thinking process, the kinds of considerations used to makeone choice rather than another, and the feelings and attitudesof the subject are neglected or given very little attention.

"... attention on the processes of thought...may alsorequire a change from testing and mass studies to those whichinvolve small numbers of subjects studied by rather intensivetechniques.

Table I

Some Fundamental Programming Concepts

1. Machine as a tool manipulated with a command language

2. Machine possessing an alterable memory

3. Literal expressions

4. Name-value associations

5. Evaluation and symbol-substitution

6. Execution of stored programs

7. Programs which make decisions

8. Procedures (algorithms)

9. Evaluation of arguments to procedures

10. Procedures as realizations of functiOlls (tran_sformations)

11. Composition of functions

12. Partial and total functions

13. Computational context (local versus global environments)

14. Evaluation in changing environments

15. Induction (recursion and iteration)

16. Dat.a structures as defined by functions

17. Problem formulation (representation)

18. Incomplete algorithms (heuristics)

Page 7

"The way in which each student looks at a particulartask may make it a unique problem for him."

-- Bloom & Broder, (1950).

It may seem obvious that to understand a physical or intellectual process

one must exercise and observe it. In fact one must observe what it does

wrongly as well as correctly before a good model of the process' structure can

be realized. Thus has error analysis proven its value in many fields (e.g.,

Fromkin, 1973; Newell & Simon, 1972). It is a basic means for evaluating

theories in all the sciences.

"Truth arises more easily from error than from confusion."

--Francis Bacon.

This work has depended upon observing children learning by making

mistakes and discoveries. For their own benefit and for the practical

requirements of research, the children had to feel motivated and supported.

Motivation is an essential precursor of effective learning, yet it is often

snubbed in the analysis of everyday ·education (Jackson, 1968); and it has yet

to be captured accurately in artificial-intelligence applications. So, apart from

examining interactions with a programming laboratory, this work has also been

concerned with the motivational aspects of tutoring, curricula, languages and

concepts.

That programming concepts provide a link between formalized thinking and

perceived reality is certainly not a new axiom (Berry, 1964). It was assumed,

perhaps tacitly, in much of the similar research quoted earlier. For motivation,

a student should look to his or her own life experience for applications of the

tools which an understanding of pertinent concepts supplies. This is the

ultimate justification for teaching programming, because the power of a

programming laboratory derives from the fact that students do more than

interact with it,they intervene, and mold the laboratory to their very own

purposes.

The research problem can be summarized by two questions: (a) How do the

characteristics of a programming laboratory influence a child's motivation and

abili ty to learn programming concepts and apply them to the solution of

problems? and (b) What are some significant features of that learning process?

2 Programming Facilities

Both experiments attempted to impart an understanding of the concepts in

Table I and fluency in two, very different programming languages. This

required the development of: (a) interactive laboratories (interpreters) for the

languages and devices used, (b) parallel curricula for teaching the concepts, (c)

means for acquiring data on each student's interactions, and (d) means for

judging each student's aptitude for programming and mastery of the concepts.

Part of requirement (a) was met easily by using existing interpreters for

two languages, Logo and Simper, developed specifically to teach children

computer programming. At one time, a third language (Spm, Appendix 1),

designed by the author, was also a candidate but was discarded. Development of

some of the devices used and requirements (b), (c) and (d) defined the work to

be done preliminary to the experiments.

Languages

The languages Simper and Logo were chosen because they are

computationally general, they are relatively easy to learn, they are interactive

with powerful editing features, and they are highly dissimilar (Figure 1). Both

are detailed extensively in report-I, so only a brief description is necessary

here. Both experiments, the first (summer-1973) and second (spring-1974), led

to changes in both languages--these will be indicated also. In the text, paired,

single quotes (') denote items in the Logo and Simper languages.

Simper was developed by Lorton and Slimick (1969) at IMSSS as a simple

simulation of an imaginary machine resembling an Hewlett-Packard model 2000.

It has been used to teach business applications of programming to students at

Woodrow Wilson High School in San Francisco (Lorton & Muscat, 1975). At

IMSSS, it has been expanded and rewritten in the Algol-60 subset of Sail

(Swinehart and Sproull, 1971) by the author.

Simper

001 :PUT A 43002 :NAME REPEAT002 lCWRITE A003 :PUT P REPEAT004 :RUN

EXECUTING 1 TO 500+++++++++++tG

...23 INSTRS IN .043 SEC.

..TO REPEAT :LETTER:@10 TYPE :LETTER:@20 REPEAT :LETTER:@ENDREPEAT DEFINED

..REPEAT "+"+++++++++++tG

I WAS AT LINE 10 IN REPEAT

004 :EDIT 1 ..EDIT REPEAT001 !CASK A @EDIT TITLE004 :SLIDE 2:7 @TITLE TO REPEAT :LETTER: :TIMES:002 :ASK B @5 TEST LESSP :TIMES: 1003 :NEGATE B @7 IFTRUE DONE004 :JUMP B .+2 @EDIT LINE 20005 :HALT 20 REPEAT :LETTER: DIFFERENCE :TIMES: 1006 :INCREMENT B @END .007 !NAME 4 REPEAT REPEAT DEFINEDSWITCHING REPEAT'S REFERENCES007 !RUN ..REPEAT "+" 10

++++++++++..EDIT REPEATEXECUTING 1 TO 500 @6 IFTRUE SKIP+10 @END++++++++++ REPEAT DEFINEDHALT...45 INSTRS IN .117 SEC.

007 lLIST

YOUR PROGRAM:

001 :CAS A002 :ASK B003 :NEG B004 :JUM B .+2 (REPEAT)005 :HAL006 :INC B007 :CWR A008 :PUT P REPEAT

..REPEAT "+" 10++++++++++

..LIST REPEAT

TO REPEAT :LETTER: :TIMES:5 TEST LESSP :TIMES: 16 IFTRUE SKIP7 IFTRUE DONE10 TYPE :LETTER:20 REPEAT :LETTER: DIFFERENCE :TIMES: 1

(These sample dialogues produce alternative programs for the repeatedprinting of a keyboard character supplied by the typist. Prompts fromSimper are the current memory address (a decimal numeral) and a ":" or an"!", depending on whether the addressed location is empty or used. Logoprompts ...... at the outer level and "@" at the editing level. .. tG" indicatesa control character typed to stop a potentially endless execution sequence.)

Fig. 1. Simper and Logo Sample Dialogues

Simper, is designed for interactive use. It is an assembly-language

interpreter for a simple decimal machine with an addressable program counter.

Its instruction set typifies those of early minicomputers and is similar to, but

simpler than, that of the language Mix (Knuth, 1970). As a programming

laboratory, Simper has three functional components: (1) a simulator for the

underlying machine (Figure 2), (2) a real-time assembler which translates

symbols and mnemonic instructions (listed in Table II) into machine language,

and (3) an interpreter which handles editing and general management of

programs (Table III). This system allows students to generate and easily

"debug" nontrivial machine-language programs. One can imagine that, when the

Simper interpreter is not running a user's program, it is simply waiting for a

message from the user which is either a phrase in one of the three languages:

machine, assembly or interpreter, or is unintelligible. The reader should

examine Figure 1 again, and then try to follow the execution of the sample

program (which realizes the function: 2x + 9) in Figure 3.

Logo (Feurzeig, et aI., 1969) is a procedural language whose basic data

structures are strings of letters or words. The Logo instruction-set is easily

expanded via procedure (operation) definitions, possibly recursive. An important

feature of Logo (as opposed to Fortran-like languages) is that operations which

a User defines are syntactically equivalent to Logo primitives. Logo contains

essentials of the currently popular Basic language as a subset,· but is superior to

Basic in terms of mathematical consistency, and clarity of phrasing and control.

Furthermore, Logo begins to address the important question of language

extensibility, which is a fundamental measure of the usefulness people can

attribute to any language for computing or thinking.

The Logo interpreter used in these experiments was obtained from Bolt,

Beranek & Newman Inc. (BBN) of Boston. It is written in Macro assembly

language for the PDP-lO. For the purposes of the experiments, Logo was

Registers (10 max.) Memory Cells (511 max.)

(programcounter)

P :

A:

B:

C*:

001:

002:

500*, 250:

Instruction Format (using righthand seven digits)

000ora

p e de g d (indirect flag & address)

r i ra s e

t t si e so r

n

(* indicates the configuration after the first experiment. The machinesimulated within the Simper interpreter operates on ten-digit decimalnumerals (words), some of which it "understands" as legal instructions.Each operation mnemonic (Table II) corresponds to a two-digit code, eachregister has a one-digit code. The address field typically contains a threedigit memory-cell designator, or register and indirect-address digits. Thevalue in register P is always used as the memory address of the nextinstruction to be executed,) .

Fig. 2. Structure of Simper's Simulated Machine

Table II

Simper Machine Operations

(* indicates operations added after the first experiment.)

Mnemonic

PUTLOADSTORE

ADDSUBTRACTMULTIPLYDIVIDEDIVIDE*

LANDLORLEXOR'

JUMPJASKCOMPARE

SHIFTROTATEEXCHANGEINCREMENTNEGATEERROR'

ASKWRITECASKCWRITElOT'

RANDOMTIMEWAIT

HALT

NOP

Action (if not obvious)

value of address field to registercopy value in addressed cell into registerinverse of 'LOAD'

add value in addressed cell to register

skip next instruction unless dividing by zeroset 'ERROR' flag. on division by zero

decimal digit-wise minimum between register and memorydecimal digit-wise maximum"exclusive or": 'LOR' except for equal digits

transfer to address if register is non-zerotransfer to address if a key has been typedthree-way skip on memory cell's value greater than,equal to, or less than register's value

flip contents of two registers

overflow error code to register

decimal numeral from keyboard to registerinverse of 'ASK'ASCII character from keyboard to registerinverse of 'CASK'input/output transfer (for graphics etc.)

random IO-digi t integer to registerseconds since midnight to registerdefer execution for milliseconds in register

stop execution

no-operation

Table III

Simper Interpreter Commands

(* indicates items added after the first experiment, ** indicates items addedafter the second experiment. Parenthesized phrases describe optionsobtained by terminating a command with the "altmode" key.)

Name

DUMP

LIST or DEBUG

RUN

GO

CLEAR**

FIX or EDIT*

FLIP**

SLIDE

SCRATCH orERASE**

FORGET or NAME

NAMES

SAVE or GET

FIELDS

FORBID or ALLOW

NEWS

HELP

control-G

GOODBYEor control-Z

Action

display decimal content of memory and registers(symbols too)

display memory content in assembly language(and machine language), 'DEBUG' shows "secret" tables

execute part or all of a program (and displayregisters)

continue execution (and display registers)

set a particular register's content to zero

change the content of one or more memory cells(and show prior content)

illterchange the contents of two cells

relocate part or all of a program in memory

erase all of a programerase all or part of a program*

erase or attach a symbol to a memory cell(alld say how much room remains for symbols)

list all symbols and their cell associatiolls(and their values)

copy memory to or from long-term storage

allow abbreviated instructions

selectively alter the machine's instruction set**

obtain the latest system news

obtain general information about Simper

stop any activity

log out

007 :LIST

001 :ASK A002 :MUL A 10003 :ADD A 6004 :WRI A005 :PUT P 1006 :9007 :008 :009 :010 :2

007 :RUN$

13:04:12

EXECUTING 1 TO 500

(the user had created the following program)

(the user runs the program, "$" denotes altmode)

(the time)

P: A: B: INSTR:-------------------------------------------1 0 0 ASK A INPUT NUMBER:4 ("4" typed by user)2 4 0 MUL A 103 8 0 ADD A 64 17 0 WRI A NUMBER=175 17 0 PUT P 11 17 0 ASK A INPUT NUMBER:O2 0 0 MUL A 103 0 0 ADD A 64 9 0 WRI A NUMBER=95 9 0 PUT P 11 9 0 ASK A INPUT NUMBER:-42 -4 0 MUL A 103 -8 0 ADD A 64 1 0 WRI A NUMBER=l5 1 0 PUT P 11 1 0 ASK A INPUT NUMBER:'G (user aborts)

... 15 INSTRS IN 1.100 SEC

007 :GO 4 (user continues a bit with no display)213

...4 INSTRS IN .042 SEC

007 :EDIT 10010 13 (the user changes the function to be: 3x + 9)007 :RUN

Fig. 3. Displaying a Simper Program's Activity

modified to communicate with various devices, including an "XY" plotter and

graphic display terminals (the total system will be referred to as IMSSS Logo).

A partial list of IMSSS Logo's primitive operations appears in Table IV,

program editing/saving commands appear in Tables V,VI and VII, and the

execution of a sample procedure is shown in Figure 4. The reader should

maintain in mind that Logo is fundamentally a prefix language--commands may

be composed of several operation calls, in which each operation is followed 'by a

list of any arguments (possibly produced by other operations) it may need in

order to be executed.

One of the few common aspects of the Simper and Logo languages is line

editing. Table VII shows the commands which allow users to correct typing and

other errors before they terminate their command-lines (causing Logo or Simper

to try to obey them). Particulary useful are the commands (control-E, -N and

·S) which allow previously stored lines or words to be injected into the user's

typing. One of the functions of good line-editing capabilities is to minimize

the burdens on the poor typist.

Finally, it should be noted that in learning to use Simper, the student must

learn the three languages (machine, assembly and interpreter) that are realized

by the system. This is not a trivial matter for naive programmers, as the

experiments have indicated.

Logo's interactive structure is more nearly unitary. Its basic piece of

executable code is a line composed of one or more commands, and its basic piece

of program (procedure definition), is an ordered series of lines. The Logo

interpreter is always executing (or capable of executing) a user's commands,

which may'call upon Logo primitives or the u,ser's own procedures. Control

returns to the user only when his or her last command and any commands it

might have called have terminated normally or been aborted. A few of Logo's

primitives may not be executed directly by a user's proc.edure, but there is not

Table IV

Some IMSSS Logo Primitives

(* indicates items added after the first experiment,** indicates items added after the second experiment.)

Name Action

TO allows creation of a new operation (a procedure)

OUTPUT allows operations to return values to the evaluatoror RETURN*or REPLY**

EDIT allows the user to change an operation's definition

MAKE associates a name with a value

VALUE* or THING accesses the value associated with a name

FRONT moves the "turtle" or train forward

WHERE returns the present location of the train

PLOT sends turtle drawing to XY plotter or robot

SAY causes the audio system to speak a message

PRINT causes the user's terminal to type a message

REQUEST asks the user for a message

SNAP makes a "snapshot" of graphics picture being drawn

MOVESNAP* moves a snapshot as part of an animated display

WORD combines two words (of letters or numerals) into one

SENTENCE combines two words or sentences into a sentence

FIRST returns the first letter or word in a value

RANDOM picks a digit between 0 and 9

SUM or ADD** returns the sum of two numbers

IS or SAMEP* are two words or sentences identical?

EQUALP are two numbers equal?

IF THEN ELSE decision making

Table V

Logo's Procedure Editing and Debugging Commands

Name

TO

EDIT

TITLE

EDIT TITLE

LIST TITLE

EDIT LINE

ERASE LINE

LIST LINE

END

LIST

ERASE

ERASE ALLPROCEDURES

LIST ALLPROCEDURES

LIST CONTENTS

LIST ALLABBREVIATIONS

TRACE

BREAK

EXIT

GO

Action

begin defining a new procedure

begin modifying an existing procedure·

redefine the name of the procedure and its inputs

change part of the title

display the ti tie

change part of any line in the procedure

delete any line

display any line

stop editing the procedure's definition

display any procedure's definition

delete any procedure's definition or trace

delete all definitions

display all definitions

display the ti ties of all defined procedures

display the user's abbreviations for all operations

display a procedure's arguments/returned valuewhenever it is executed

halt execution (same as control-G)

halt and print a message

continue execution

(Indented commands may only be given after editing has been begun with'TO' or 'EDIT'.)

Table VI

Logo's File-manipulation Commands

Page 20

Name

SAVE

GET

LIST FILE

LIST ENTRY

LIST PROCEDURES

LIST CONTENTS

Action

replace an entry on a file with the currentcontents of memory

append the content of an entry to memory

display the entry names in a file

display everything in an entry

display only the procedures in an entry

display the titles of an entry's procedures

LIST ABBREVIATIONS display the abbreviations in an entry

ERASE ENTRY

COPY

delete an entry from a file

copy a text file to or from a file entry

Table VII

Simper/Logo Line-editing Commands (* means Logo only.)

- Name Action

control-A or erases the previous character typedrubout

control-W erases the previous word typed

control-X erases the whole line (also control-U in Simper)

control-R retypes the present line minus deletions

linefeed continues a line beyond 72 characters

return or terminates- a line (altmode is also known as "escape" oraltmode "enter")

control-N* insert (into the present line) the next word from theprevious (or edited) line

control-S* skip the next word from the previous (or edited) line

control-E* insert everything remaining in the previous (or edited)line into the present line

(An example of Logo procedure editing:

..TO WELCOME@1O SAY "HELLO THERE"@EDIT LINE 10 (causes the line number "10" to be printed and

inserted into Logo's input buffer just as ifthe user had typed it, so it may be erased.Logo has now also grabbed the existing text ofline 10 and knows 'SAY' to be its first word)

@10 [ 01]20 fNsay "fSfNthere" [ "] GOES A WELCOME"

(The above edi ting line produced line 20 by·using line 10. I1tll means "control-", Logo'styping is in lower case, deleted characters arein brackets)

@LISTTO WELCOME10 SAY "HELLO"20 SAY "THERE GOES A WELCOME" (the new line)

@)

+-LIST ACKERMAN (the user had defined the following procedure)

TO ACKERMAN oX: :Y:10 IF EMPTYP oX: THEN RETURN WORD oX: "Y"20 IF EMPTYP :Y: THEN RETURN ACKERMAN BUTFIRST :X: "Y"30 RETURN ACKERMAN BUTFIRST oX: ACKERMAN oX: BUTFIRST :Y:END

which realizes a" string example of Ackerman's function)

TRACE ACKERMAN ('TRACE' will allow the user to follow ACKERMAN'sexecution history, observing its arguments when it iscalled and the values it returns when it is done.Recursively generated copies of 'ACKERMAN' aredenoted by indentation)

+-PRINT ACKERMAN "XX" "Y" (execution begins)ACKERMAN OF "XX" AND "Y"

ACKERMAN OF "XX" AND ....ACKERMAN OF "X" AND "Y"

ACKERMAN OF "X" AND.... (.... is the empty string)ACKERMAN OF .... AND "Y"ACKERMAN RETURNS "YY"

ACKERMAN RETURNS "YY"ACKERMAN OF .... AND "YY"ACKERMAN RETURNS "YYY"

ACKERMAN RETURNS "YYY"ACKERMAN RETURNS "YYY"ACKERMAN OF "X" AND "YYY"

ACKERMAN OF "X" AND "YY"ACKERMAN OF "X" AND "Y"

ACKERMAN OF "X" AND ....ACKERMAN OF .... AND "y"ACKERMAN RETURNS "YY"

ACKERMAN RETURNS "YY"ACKERMAN OF ,n, AND "YY"ACKERMAN RETURNS "YYY"

ACKERMAN RETURNS "YYY"ACKERMAN OF .... AND "YYY"ACKERMAN RETURNS "YYYY"

ACKERMAN RETURNS "YYYY"ACKERMAN OF .... AND "YYYY"ACKERMAN RETURNS "YYYYY"

ACKERMAN RETURNS "YYYYY"ACKERMAN RETURNS "YYYYY" (to PRINT)YYYYY+-

Fig. 4. Tracing a Logo Procedure's Activity

Page 22

a strict distinction between sets of commands as exists in Simper's three-level

structure. However, a quirk in Logo's evaluation scheme imposes a different

syntax on editing and management commands versus other operations. This will

be discussed later. Readers interested in more detailed discussions of Simper

and Logo should refer to report-I.

Peripheral Devices

Various terminals and controllable devices were available to Logo and

Simper students during and after both experiments (Figure 5). The machine

language Logo interpreter was modified to dispatch graphics (or other special

device) commands to a Sail program: Sailogo (Figure 5). This program and

Logo acted as coroutines. Hence, Logo's control of special devices was realized

by Sail procedures.

Most special devices played a relatively small role in the work reported on

here. A brief summary of only the graphics and animation facilities will be

included. All the devices are fully documented in report-I.!

Both experiments sought to establish good examples of how each device

could be employed in solutions to programming problems. Some aspects of this

will be discussed later with emphasis on relating device capabilities to teaching

the concepts (e.g., those in Table I).

All the students whose work will be discussed here began their

programming at conventional, model 33 Teletypes(R). This slow (IO-characters-

per-second), noisy, inexpensive but reliable terminal was their basic means for

communicating with Logo and Simper until they had mastered the languages

well enough to make good use of such special capabilities as graphics. In spite

11 am indebted to Steve Weyer for his fine implementation of the many special IMSSSLogo features, such as graphics and animation.

PDP-lO Operating SystemIII

IMSSS Student System/ \

/ \/ \

Logo ----------- Simper/ \ \ I .

/ \ \ II \ \ I .

.TEC(R) Sailogo -------.--------1-----.--I \ . \ I .\I \ \ I . \

. I \. \ I .\Turtle Audio Train Plotter Teletype(R) IMLAC(R)

(Dotted lines mark connections made after the first experiment)

Fig. 5. Programming System Structure

of obvious drawbacks, Teletypes were in plentiful supply and provided paper

printout for projects (like posters) whose results students wanted to take home.

Some students retained a particular liking for Teletypes, because the mechanical

bedlam generated by one in operation fascinated them.

Some fast (a few hundred characters-per-second), text-oriented, video

displays were used occasionally by some students. These had limited, graphics

like capabili ties, but they were not exploited in the experiments.

In the first experiment, two groups of students used IMLAC(R) PDS-l

graphics displays exclusively. These groups, however, are discussed only in

report-I. For the students whose work is of interest here, the IMLAC displays

constituted a goal, attained when a student's proficiency in the languages was

adequate to allow comfortable use of the graphics system (Tables VIn and IX).

The graphics, line-drawing system emulates many abilities of the robot

"turtle" developed at MIT and BBN (Feurzeig and Lukas, 1972b). It allows

movement on the screen to be specified by "x,y" end-points in addition to the

turtle's normal, roving-polar-coordinates scheme (in which movement is specified

by 'FRONT' and 'BACK' along an angular heading changed by 'RIGHT' and

'LEFT'). For example, a square can be drawn by the Logo procedure 'SQUARE':

TO CORNER :SIZE:"10 FRONT :SIZE:20 RIGHT 90END

TO SQUARE :SIZE:10 CORNER :SIZE:20 CORNER :SIZE:30 CORNER :SIZE:40 CORNER :SIZE:END

Name-

CLEAR

WIPE

SEE (HIDE)

PENDOWN (PENUP)

PENP

POKE (UNPOKE)

HOME

FRONT (BACK)

LEFT (RIGHT)

SETHEADING

ASETX (ASETY)

ASETXY

RSETX (RSETY)

RSETXY

THERE

HERE

ARC

ZAP (ZIP)

PLOT (UNPLOT)

SETSCALE

SETTURTLE

WRAP

COMPRESS

Page 26

Table VIII

IMSSS Logo Turtle-Graphics Commands

Action

erase the text area of the screen

erase any drawing and put turtle home

make the turtle appear (disappear)

enable turtle to draw visible (invisible) lines

return '"TRUE''' if turtle's pen is down, '"FALSE''' otherwise

stick out (pull in) turtle's head

move turtle to home position defined by 'SETTURTLE'

move turtle forward (backward) a specific distance

rotate turtle left (right) specific number of degrees

point turtle on a specific angular heading

move turtle horizontally (vertically) to an absolutescreen position

move turtle horizontally and vertically to a position

move turtle horizontally ( vertically) a relative amount

move turtle relative to its present screen position

equivalent to an 'ASETXY' and a 'SETHEADING'

return turtle's current position and angular heading

make turtle draw an arc of specified radius and sense

erase last turtle move(s) up to a visible line segment

(do not) direct turtle commands to rohot or plotter

set screen resolution in units-per-inch

set both sca~e and home positron on screen

set up screen boundaries for wraparound

shorten IMLAC display list (precludes use of 'ZAP' oi 'ZIP')

Table IX

IMSSS Logo Animation Commands

Name

SNAP

ENDSNAP

ERASESNAP

WHATSNAPS

SHOWSNAP

PUTSNAP

MOVESNAP

WIPESNAPS

Action

wipe screen and begin creating a numbered "snapshot" ofwhatever drawing (less erasures) is subsequently done

finish defining current snapshot and wipe screen

delete specified snap and its number

return a sentence of currently used snapshot numbers

display specified snapshot at turtle's screen position

identify a snapshot with an old or new "object" at aspecific screen positionJ or move or erase an object

. move an object (with wraparound) a relative distance ona relative heading and return object's final, absoluteposition (lOR" in an object number has effect of 'RSETXY')

wipe screen and erase all snapshots and objects

(A procedure for moving an object, referenced by a snapshot number, across the screenmight be:

TO WALK :SNAPNUMBER:10 SHOWSNAP :SNAPNUMBER,20 ZAP (a snapshot is a "line" under erasure)30 FRONT 1040 WALK :SNAPNUMBER:END

or, better:

TO WALK :OBJECTNUMBER:10 MOVESNAP:OBJECTNUMBER: "10 0"20 WALK :OBJECTNUMBER:END

for the latterJ 'PUTSNAP' must first be used to tie a snapshot (an appearance) to an objectat some screen position.)

Lines drawn may be erased by 'ZAP' and 'ZIP' commands, permitting limited

picture editing as well as primitive animation. One student produced a short

sequence showing a fuse "burning" down (disappearing into) and exploding a

firecracker..

'PLOT' allows one to direct the effects of most graphics commands to either

an HP7202A plotter or a robot turtle (General Turtle Inc., Cambridge, Mass.).

Most students highly valued the .abili ty to reproduce on paper what their

programs had drawn on the display screens. Since students could use any type

of terminal and stiI! have their drawings appear on the plotter, this was

exploited to encourage students to write and debug storable procedures rather

. than to just draw by direct commands. The plotter was only sporadically

available during the first experiment and a true, robot turtle was available on

occasion during both experiments. The robot came along with a "music-box"

which was used significantly by two students in the second experiment.

During the first experiment, it became apparent that more powerful

animation abilities would be possible and might serve as strong motivation for

more complex student projects.. Prior to the second experiment, genuine

animation was added to Logo and Simper was modified to access the graphics

system as well (Appendix 3, pages 1ST and 1LT). The 'SNAP' command aI!owed

a student to save the effects of most subsequent graphics commands as a display

subroutine within the IMLAC. These "snapshots" could then be shown

anywhere on the IMLAC screen with 'SHOWSNAP' or 'PUTSNAP'. Snapshots of

the same object in different orientations or sizes could then be shown

successively in a "movie" (e.g., with 'MOVESNAP').

Although true animation CPUTSNAP' and 'MOVESNAP' in Table IX) was

not used by students in the first experiment, it was used in the second. Some

students from the first experiment continued to work with Logo, influencing

(

Page 29

some aspects of the developing animation system. A short film about

LogolIMLAC graphics and animation is available from IMSSS.2 Figure 6 is

adapted from that film.

Students used animation to produce such things as a flyable helicopter, a

rocket launch, animated tic-tac-toe, movies of throbbing polygons, and a tennis-

game. An example program appears in Appendix 4.

The computer could also be made to utter sounds (via the Logo primitive

'SAY') composed of any of several thousand prerecorded phrases, words, and

phonemes stored in the IMSSS system. No organized use was made of this in

the experiments, since it amounts to little more than the aural equivalent of

'PRINT'. Only a few terminals with audio output were available to students.

Nevertheless, most students discovered the facility and some made imaginative

use of it.

Fig. 6. Successive FraInes from a Logo-Animation "Movie".

2 pat Crawley of the Stanford Communications Department produced this film. starringAdam Grosser, Greg Hinchliffe, Steve Spurlock. Steve Weyer and the author.

3 Students, Tutoring and Curricula

The desire to draw some conclusions about programming languages led to

the student groupings shown in Table X. The first experiment had been

concerned with assessing the value of graphics as welI, accounting for the

formation of groups IV and V. Those two groups are discussed only in report-l.

Groups I, II and III in both the first and the second experiments provided most

of the data for comparing the languages, evaluating the curricula and

characterizing tutor-student-machine interactions.

The first experiment influenced many aspects of the second, some of which

will be discussed here. For example, the enthusiasm generated by the graphics

and animation system inspired the inclusion of graphics in late parts of both

the Simper and Logo curricula, at a time when students had mastered either

language "welI enough".

Schools near Stanford were contacted in order to obtain inexperienced

programmers, 10 to 15 years old--an age which is thought to ensure that

children can master abstractions (Piaget, 1970).1

Teachers and others recommending students were asked not to base their

selections on students' performances in school, because the intent was to study

how any child learns to program. It had been observed previously that teachers

tend to recommend only their better, mathematics students for such special

projects. Apart from an admonition against such preference, the manner in

which the invitation "to learn how to use a computer" was presented to students

could not be controlIed, so it cannot be stated that the enrolIees constituted a

cross-section of local students.

11 am indebted ~o Carolyn Stauffer for her invaluable help as liaison.

Table X

Experimental Groups

Group Composition

1973:

1974:

I

II

III

IV

V

I

II

III

8 students learning Logo and then Simper

8 students learning Simper and then Logo

8 students learning Logo and Simper at once

5 students learning Logo with graphics

10 paired students learning Logo with graphics

5 students learning Logo and then Simper

5 students learning Simper and then Logo

5 students learning Logo and Simper at once

In the second experiment, an additional source of "gifted" students was

available. They worked at teletypewriters at home, were assigned to groups

matching I, II and III, received the corresponding curricula on demand by mail

and could call myself or others at Stanford for help during certain hours.

Unfortunately, only a few of these students did significant amounts of work

with Logo and Simper. Their work will be discussed at appropriate times, but

these students are not indicated in the Tables and Figures.

More students responded than were needed for the groups outlined in Table

X. As many as possible were accommodated, including friends who appeared

later during the body of the experiments. Figure 7 presents some responses of

the enrolling students to a brief questionnaire. Since students typically heard

about the course from their matbematics teachers, the indicated preferences

weren't surprising. As an aside, the students' attitudes toward school seemed to

agree with observations in Jackson (1968) that one-fifth or more of all school

children will readily admit that they dislike school in general.

In all, about fifty students involved themselves in the first experiment, and

correspondingly, about twenty enrolled in the second. To some degree, this

insulated the experiments from the problem of dropouts. Transportation

problems created a few defacto dropouts, particularly in the first experiment.

In the first experiment, students were scheduled to use the machine one

hour per day, four days per week, with more regard for their convenience than

for experimental grouping (Table X). Because the first experiment was in part

a pilot study for the second, Fridays were reserved for modifying the curricula

and debugging the interpreters or devices. However, on demand of some of the

more interested students, Friday was considered open too.

Age/School Distribution Age/Liking of School

ch lO- st; 10I pe wo 14 15 15d hv la gu 14 14 15r hv me gu 14 14 14e 5- hv hv rna 14 13 13n hv hv rna 14 13 13 12

hv hv rna gu 12 13 12 12fr hv hv hv rna gu 13 11 13 12 12hv hv hv hv rna gu 11 10 10 12 12

0- ---------------------- --------------10 11 12 13 14 15 1 2 3 4 5

age disl ike lik.e

Age/Subject Preferences

Engl ish Languages Mathematics Science

1515- 14

14141313

10- 15 14 15 15 1314 14 14 15 14 1314 14 14 15 14 14 15 1314 14 14 15 13 13 14 15 1213 13 14 14 12 14 13 13 14 12

5- 12 15 13 14 13 15 14 12 14 13 12 14 1212 14 12 13 13 14 14 12 14 12 12 12 14 1212 14 12 13 15 12 13 13 12 14 14 13 12 12 12 14 1211 14 12 12 13 12 13 12 12 13 14 13 12 11 14 12 13 1111 13 10 10 12 10 13 11 11 10 12 12 11 10 14 11 10 13 10

0- -------------- -------------- -------------- -- -- -_._-- -----1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5

dislike like

Fig. 7a. Some Information Characterizing the 1973 Students

Age/School Distribution

ch 10-i1d wor te woe 5- te ten hv te

hv tehv hv te

ba wo hv hv te0- ----------------------

9 10 11 12 13 14

age

Age/Liking of School

141413131313

12 1211 12 12 13

9 12 12 13-----_._-------

1 2 3 4 5

dislike like

Page 34

Age/Subject Preferences

Engl ish languages Mathematics Science

10- 141313

14 13 1413 13 13

5- 13 13 1314 13 12 14 12 14 13 13

14 13 12 13 14 12 12 12 13 13 1212 13 13 12 12 11 13 13 12 13 12 12 12 12 12

9 12 13 11 12 9 12 12 12 13 12 12 11 9 12 11 9 120- -------------- -------------- -------------- --------------

1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5

dislike lik.e

Fig. 7b. Some Information Characterizing the 1974 Students

In the second experiment, students used the machine three hours per week,

on two-or three-day schedules. This was done because the first experiment had

indicated that students should be segregated by group to allow more uniform

tutoring and to minimize the inevitable distractions raised in a roomfull of

students working at different places in different curricula or on projects in

different languages. The students still retained the right to go to another

room, after their scheduled session had ended, and use another terminal.

In order to obtain an initial assessment of each student's aptitude for

programming, and to point out possible problems that each student might later

have in learning the concepts, a test was constructed prior to the first

experiment. It consisted of questions gleaned from a wide range of sources,

because no one test in current use seemed to be valid for the range of concepts

in Table 1. A number of commercial programming tests were examined and

some questions from these were used.2

However, all these tests relied heavily on timed sections of multiple-choice,

often repetitious questions. Such structuring produces easily graded results and

is commonly used to boost the "reliability" (correlation among test applications)

of a test. In contrast, development of the test used for this work placed

emphasis on the more elusive but crucial notion of validity, and on the

exposure of thought processes (e.g., per Bloom & Broder, 1950).

A test, no matter how reliable, is utterly useless if it fails to measure the

property of interest. It may even be dangerously misleading. In terms of the

theory of testing and evaluation, as currently applied in the social sciences (e.g.,

see Worthen & Sanders, 1973; or, for the politics/reali ties of evaluation, see

Jackson, 1968, and McLaughlin, 1974), validity like reliability is measured by

21est5 included: the ARea Computer Programmer, the CPAB and Flanagan Industrial Testseries by SRA, the fePI data-processing test. and the IBM programming aptitude test.

correlative techniques. However, no matter how long the chain of correlations,

validity is ultimately founded in human judgements and evaluations of quality.

An example of validation taken from a commercial test-brochure is outlined in

Appendix 2. It should alert the reader to some of the pitfalls that threaten

those who wish to do aptitude testing, particularly with commercially available

materials. Read critically, the example implies that testing theory and practice

typically diverge when validity is demanded, yet validity of measures is

precisely what must be demanded when meaningful research is the goal.

A test was presented to enrolling students for two purposes. One, some

measure of the students' aptitude for learning the concepts was needed for

matched grouping. Two, hopefully it would be possible to match the way

students attacked particular questions in the test with particular aspects of

their performance in the experiments. The test might ther,efore shed light on

the .tutorial needs of each student.

The preliminary test was constructed of some questions taken from the

commercial tests mentioned earlier and questions of original design. All

questions were formulated or reformulated to require constructive answers. The

1973 and 1974 tests are reproduced in report-1 and Appendix 2, respectively.

Multiple-choice questions were thought useless. They force students to make

judgements based on two levels: their relevant knowledge and the sensibility of

the prescribed answers. The grader of such questions is freed of the burden of

judging diverse answers simply by having it thrown onto the test constructer

and the least-experienced judges: the students. What students think about each

question and why they give their answers are important pieces of information

that such testing destroys. For this work, students' answers were valued even if

they were wrong or incomplete. Detailed answers would help evaluate the test

as well as the students; and the judging would be done by persons experienced

in the relevant fields (i.e., by the author or other programmers).

The desire for constructive answers to all questions on the test is best

justified by those examples of "wrong" answers which nonetheless showed that

students were thinking along the right lines. Figure 8 presents some for a

question derived from a commercial test (note also the subtle defects in

drawings Band C, and the beguiling A-B sequence). It is important to note

that answers like those in the figure evidence approaches to the questions which

would have been counted completely right or wrong if nonconstructive answers

(e.g., multiple-choice) had been required. Figure 9 shows examples of totally

unexpected answers to a question of original formulation.

One can neither assess a student fairly, nor know what a test is testing if

. the questioning scheme critically warps or limits information relevant to the

purpose test.

About one-hundred questions were selected for possible use in the test.

Before the questions were presented to students enrolling in the first

experiment, their difficulty, clarity, and the time required for their solution

were evaluated by presenting the entire assemblage to several programmers

(children and adults) in the IMSSS community.3 As a result of this simple

evaluation, most of the questions were accepted and were presented in two tests.

Students answered one-third of the questions on the day they enrolled, being

allowed one hour. The second test was to be completed at home at each

student's convenience. The two parts of the test contained many similar

questions. This was done because the preliminary evaluation had suggested that

time should not be a factor in testing. Thorough and accurate evaluation of

both test and students seemed to demand that as many questions as possible be

answered. Two-part testing would also suggest whether or not any time limit

should be applied to the single test which would be used in the second

3 1 am g~ateful to Marney Beard. Doug Danforth. Adele Goldberg. Paul Hechinger. GregHinchliffe and Lauri Kanerva for their help.

The Question and the Desired Answer:

Figure A was changed into Figure B by iI simple rule. Please drawfigure D so that it corresponds to figure C changed by the same rule.

A B c D

What is the rule in words?

Other Answers:

BOTTOM SHRINKS, TOP GROWS

TURN IT UPSIDE DOWN AND ALTERNATE SIZEol:J

A IS A SQUARE WITH A CIRCLE, B IS JUST THE OPPOSITE

YOU CHANGE TO THE OPPOSITES

TAKE THE FIRST BASIC FIGURE AND CHANGE WITH THESMALLER AND TURN UPSIDE DOWN

THE SMALL TOP FIGURE BECOMES LARGE AND THE OTHERBECOMES SMALL AND THEY. TRADE PLACES

Fig. 8. Some "Wrong" Answers from the 1973 Preliminary Test

The Question and the Desired Answer:

What one rule, not using arithmetic, was used to make the digits onthe right from the strings of digits on the left?

999999999

556

6106

TAKE THE FIRST DIGIT

Alternate, Unforeseen Answers:

THE DIGIT USED THE MOST

PREDOMINANT NUMBER

9

5

6

WHAT EVER NUMBER THERE IS MOST ON THE LEFT, PUT ITON THE RIGHT

TAKE THE DIGIT WITH THE HIGHEST PLACE VALUE,OR THE ONE THAT REPEATS MOST OFTEN

Note: "number" was acceptable although "digit" or "numeral II weretechnically correct. More than half of the students who gave·complete answers to this problem seemed not to be aware of thedistinction. Their rank and choices of words contrasted as:

1973 or 1974student rank

at or above median

below median

"digit tr

or~Inumeral"

14

3

"number"

11

13

Fig. 9. Some Novel Answers from the Preliminary Tests

experiment. Unfortunately, many of the students failed to complete the lengthy

"take-home" portion of the test, either for lack of interest or because they

dropped out. For the second experiment, it was decided that the test would be

shorter and that new students would work on it during their first day, taking

it home to finish if necessary.

Questions had been selected according to their apparent value in testing the

ability to manipulate unfamiliar languages, model or analyze processes, form

deductions, and visualize figural transformations (see Appendix 2). Some of the

questions proved to be very useful for discriminating among the enrolling

students. Two of these, the "candy-machine" and the "numbers-in-boxes"

problems (Appendix 2, or report-1, page 169), required an understanding of

concepts directly related to programming. Errors made by the students on these

two questions were especially interesting and will be discussed.

In the candy-machine problem, a partial flow-diagram was provided in

which few states had been left blank and connections between some states were

missing. The task was to complete the diagram in any reasonable way. Many

students had trouble with the basic idea that a process can be represented on

paper as a diagram of the sequence of events in the process. They left blank

states empty, filled them inappropriately, or misconnected the dangling states.

Errors in the solutions given could be divided into three classes: (1)

assignment of unreasonable destinations for unconnected arrows, (2) assignment

of unreasonable functions for undescribed states, and (3) treatment of the entire

diagram as a maze in which only one path was to be marked as a likely

protocol. Errors in class (1) or (2) suggest that a student had trouble using

the information alrell.dy present in the diagram to deduce reasonable "things to

do next" or "things to do now". Class (3) is interesting because such errors

indicate that a student viewed the diagram as a menu of instructions from

which to choose one plausible sequence, rather than as a complete description of

all possible sequences, for some process.

The numbers-in-boxes question asked the students to obey a short, program

like sequence of arithmetic instructions which operated on some numbers

written in a set of numbered boxes. Very few students correctly obeyed the

instruction which read: "Add the number in box 7 to the number found in the

box whose box number is in box 6, and write the sum in box 6". The sentence

is hard to read, but the idea that a number (value) in a box could be used as

the number (name) of a box (indirect addressing) was the typical difficulty.

Many students also had trouble with the idea that writing a new number into a

box should destroy its previous contents. Solutions fell into a few distinct

classes which can be attributed to failures in the understanding of those two

concepts.

In both experiments, the test was used to establish a rank ordering of

enrolling students, and performance on the test seemed to break into a few

levels. For the first experiment, roughly equal numbers of students from each

level were assigned to groups I, II and III. The second experiment's grouping

was more constrained by the interaction of students' scheduling preferences with

the desire to keep the groups in separate time-slots. In both experiments

students determined their own class schedule within the time constraints

mentioned earlier.

Figure 10 shows the composition of the groups according to testing rank,

age and amount of time spent in actual work with the interpreters. The candy

machine and the "logic" (Appendix 2, or report-I, page 170) problems tended to

be most influential in discriminating among students of equal age above and

below the median. The youngest had the most trouble with the candy machine.

They missed the poi~~ that the diagram was an overall description of the

machine. A few of the older students were familiar with flow-charts from

school and thought that problem easy. In the first experiment, they had also

been students who enrolled late. These late arrivals usually did very well

Group Age

Page 42

Hours Spent Using Logo & Simper

III*$ 151$ 15II*$ 15Ill$ 13III* 131*$ 12II*$ 13Ill# 141# 14II.............. 13II 14II 12II# 14II*# 141# 14

median.. 1# 14II# 14I 11II# 14III 11I 12I 14III*# 13III 12III 131$ 121* 10II 12III 12I 12Ill$ 10II 13

36.435.718.129.711.112.759.2o5.8

50.633.522.8

6.427.9

5.75.7o

24.24.9

14.223.018.0

2.111.028.727.111.721.120.119.135.7

6.1

* marks students who enrolledlate.

# marks early dropouts.

. marks significant breaks inperformance on the test.

$ marks those who continuedprogramming well beyond theexperiment.

Fig. lOa. Student Ranking on the 1973 Preliminary Test

Group Age

Page 43

Hours Spent Using Logo & Simper

1$ 12III$ 9III* 13III 12II 13II 13II.............. 131* 12

median.. II$ 13II 111$ 141# 13IlL 14III 12III* 121# 12I 12

24.247.827.133.215.426.925.926.333.714.345.4

3.212.038,616.21.58.0

* marks students who enrolledlate.

# marks early dropouts.

. marks significant breaks inperformance on the test.

$ marks those who continuedprogramming well beyond theexperiment.

Fig. lOb. Student Ranking on the 1974 Preliminary Test

with the test, perhaps in part because they worked on it quietly alone--a

feature lacking in the massed testing of the first enrollees. This provided

another reason for eliminating timing of the test in the second experiment.

Examining the first experiment's test-results in terms of four constituents:

the first three problems mentioned above, and everything else, the students'

performances compare generally as follows. Students at the bottom of the

ranking (Figure lOa) were unable to grasp the candy-machine and the box-

program questions, they correctly analyzed only the clearest statements in the

logic problem, and they failed to finish the test by a large amount. Students

near the middle filled only the empty states in the candy machine reasonably;

they correctly obeyed all commands but the indirect-addressing command in the

box program, with some failures to erase a box's content when they wrote into

it; they only missed the fourth statement in the logic problem; and they did

fairly well on the rest of the test, though not always finishing it. Students

near the top correctly filled all states and connected all the dangling arrows in

the candy machine, a few of them missed the indirect-addressing command in

the box program, they did the logic problem correctly, and they typically

finished the rest of the test. Similar comments apply to test results for the

second experiment, with the qualification that these students seemed to do

better on the test than did those in the first experiment.

Of course these breakdowns are not rigid. In particular, it is very hard to

order many of the tests in the broad middle regions of the rankings. Ranking/'.

forces transitivity upon performance ratings for solutions and problems which

are often qualitatively different. But by demanding constructive answers, the

answers contained much detailed information about the students and the test.'.If the test had been an exercise in multiple-choice, it is not clear what

information it would have conveyed, but it certainly would have conveyed less.

Some changes in the test were made as a result of the first experiment.

Aside from making it shorter and unitary, and applying it individually with no

time limit, changes typically involved readability and the elimination of

frivolous questions.

Tutoring. Both experiments were planned to depend upon written curricula

which would control the basic information given to students. Interpreters for

the programming languages would simply act as computational .resources which

the students could use to work problems in the curricula or experiment with on

their own. However, any attempt to develop a fully self-contained curriculum

for programming was deemed unrealistic. The main concern was gaining access

to tutorial protocols generated by novice programmers working in the best

possible environment for learning. Therefore, human tutors were provided who

could help students over failures in the curricula and report their interactions.

The -tutors were to be knowledgeable in the programming languages being taught

and would be familiar with the corresponding curricula.

In the first experiment, it was hoped that enough tutors would be available

each day to guarantee at least one for each five students in each group.4 Two

instructions to the tutors were emphasized: (1) never type anything for the

student on his or her own terminal, even when giving the most direct help, all

typing must be the student's; and (2) when asked for help on any problem,

encourage the student to formulate and tryout his or her own ideas first,

before making other suggestions. It was hoped that these instructions would

guarantee the purity of the protocol data and help the students to think as

much about generating and debugging ideas as about getting correct results.

Unfortunately, this tutoring effort failed in some crucial functions. First,

4 My thanks go to Avron Barr. Marney Beard, Doug Danforth, Adele Goldberg., David Ragosaand John Shochfor their help as tutors.

initial enthusiasm faded quickly and most tutors became sporadic in making

their scheduled appearances. This seemed largely due to their lack of prior

experience in working closely with, and at the immediate demand of, several

children at once. Second, and accordingly, the tutors could not maintain

detailed logs of their interactions. Third, the tutors did not always keep up

with new developments in the curricula, partly because its production fell

behind the students' pace and partly because pieces of it were designed "on the

fly" to patch mistakes/omissions. In either case, new curriculum-text was made

available to students and tutors simultaneously--a bad policy.

Therefore, for the second experiment, tutoring was to be done by one

. person (the author) working with at most five students, all in the same group

(per Table X), with the appropriate curriculum ready well in advance of each

session. This facilitated note taking, gave the students personal, more uniform

help, and ensured that problems with the curricula/interpreters were caught

quickly. It is one reason why the number of students in the second experiment

is smaller than it was in the first.

Curricula. Development of "parallel" curricula for Simper and Logo proved

to be the most demanding task in setting up the experiments. Both the

concepts and the languages had to be taught, and this is done best with example

problems, some of whose solutions students must copy, modify or generate. The

ability to teach both the concepts and the languages would be very sensitive to

the choice of problems. For the students, the experiment was to serve to

improve their literacy on the subject of computers and computation. Again the

choice of examples and projects would be important.

Unfortunately, documentation of problems used in similar work by others

was scarce or cursory. Furthermore, most of the relevant research had been

based on Logo or an equivalent high-level language. Problems appropriate for a

low-level language such as Simper are typically quite different. That was the

fundamental obstacle to achieving apparent parallelism, given the intentionally

diverse natures of the languages to be taught. So, the curricula were

constructed to teach the concepts in roughly the same. order, using whatever

features each language possessed that could best be exploited for each concept.

As well as the concepts, the mechanical details of each language had to be

taught. A few features (line-editing, Table VII) of Simper and Logo are very

similar and were taught at the same time in the same way. But most features

were taught differently, either because they were appropriate to different

concepts or because they were needed at different times as tools in the general

structure of each language. The Logo and Simper curricula are documented, as

they were during the first experiment, in report-I. The discussion here will

concentrate on the changes to the curricula which resulted from that

experiment, in preparation for the second (see also Appendix 3).

Each curriculum was divided into five logical parts, each typically

discussing more than one concept. Each part gave students programs to work on

and fill-in-the-blanks questions to answer. The parts were distributed one at a

time, giving the author a chance to review each student's work on them. Those

students learning Simper and Logo simultaneously (group III) alternately

received parts for each language.

The concepts were presented only very roughly in the order of Table 1.

For instance, the concept of a heuristic was introduced relatively early via a

scheme for thinking about recursive algorithms. This involved a brief case

analysis of some problems (derived from Polya, 1957): (a) what case can be

computed? Cb) how.do I detect that case? Cc) if not that case, then how do I

generate one closer to it? Cd) what must I remember for each case? and Ce)

when do I stop? In procedural terms, Ca) and Cb) form the procedure body, (c)

is the recursive step, Cd) preserves local context, and (e) is the stopping rule.

A special effort was made to produce visually pleasing curricula. Path

pointers gave direction to the student, making the next question or instruction

contingent upon the student's latest response. This subtly introduced decision

making and sequencing (program control). It was, however, a bit too subtle for

most students. Cartoons and examples were chosen for humorous as well as

conceptual merit, and summaries were included so that the curricula could

endure as reference material.

Changes in the curricula between the two experiments centered on

reordering and reformulation of discussions of several concepts. One effect was

reduction of the sizes of both the curricula to roughly sixty pages (a reduction

of 1/3 for Simper and 1/5 for Logo).

Modifications to the Simper curriculum were based upon apparent student

confusions in the first experiment. In Part 2, an explicit reminder was added

as to why computers don't understand human languages (because humans

themselves have yet to comprehend their own faculties). This helped to clarify

the curious results students obtained when they followed the advice to "type

anything you please". Otherwise, Parts 1 and 2 remained unchanged (see

report-I). Parts 3, 4 and 5 then proceeded along a mostly new course in

covering material previously allocated a dozen parts.

The new approach hinged on teaching machine-language first and thereby

motivating both the desirability of the more convenient assembly-language and

the need for the interpreter's powerful editing language. All this was

permeated with allusions to message processing and computational context. The

former being a metaphor used with some success in tutoring experiment-1

students, and the latt"i,r being an essential concept that had been troublesome to

many of those students.

Part 3 first sought to clear up the lesser problem of what literals are in

the language by demonstrating more examples. It also tried to motivate the

need for registers as a scratch pad. It then approached one aspect of context:

attention. The machine was described as giving its "attention" to registers and

memory cells when in the process of executing a program--only certain values in

those cells could be "understood" as legal instructions. Without an ability to

focus its attention on a source of messages, the machine would be quite useless.

Registers, as defined by the machine's structure, were described as a means for

passing messages between instructions, reflecting an aspect of the machine's

internal context. In spite of the simplicity of the machine-language programs

written in Part 3, editing commands such as 'SLIDE' (Table III) found direct

application; and a few students suggested new ones (e.g., 'FLIP').

Simper Part 4 reviewed two of the three segments of machine-language

instructions covered in Part 3 (i.e., the operation and register fields), and went

on to motivate the need for the address field as a source of the second input to

binary operations (e.g., addition) and as a means for accessing "full-word"

chunks of data. Since the structure of most machines modelled by Simper was

once dictated by both technology and economics, a brief word to that effect was

included in the tutoring. The essential role of memory in any machine

deserving of the name "computer" was alluded to. Using a time-telling program

developed in this and the previous part, students were led into assembly

language. The use of new editing commands (e.g., 'LIST'), designed especially

for this second language, were also introduced. The remainder of Part 4 dealt

with execution sequencing, and decision making. It attempted to motivate these

wi th an odd!even number-testing program analogous to one used in the Logo

curriculum. This problem was formulated as a test of the student's ability to

translate an English "statement of a program into Simper. Students having

trouble writing the program were helped, and details of this tutoring were

recorded. The final version of the program demanded an understanding of

literals, names (in the form of machine addresses), binary operations, register

and memory-cell intercommunication, conditional and unconditional branching,

and the communication of symbols to and from the typist. To cap off this

work and prove that problems can often be solved in several externally

equivalent ways, the curriculum suggested rewriting the program with fewer

instructions (three basic forms existed).

Simper Part 5 attempted to crystallize the idea that interactive programs

define new languages and thus set up new contexts when run. Student-defined

symbols (names) and relative addressing were introduced as conveniences,

peculiar not just to assembly-language programming. They found application in

a random-number, guessing-game program used also in the Logo curriculum.

The decision-making operation ('COMPARE') was then introduced as a way of

making the students' programs smarter--they could now give their users hints

like: . "GUESS HIGHER". At this point, the concept of a function was

introduced much as in the original curriculum and with the same visual aids.

Part 5 closed with some reviews of messages and context in terms of the

"domains" of functions.

Now students could go on to learn how to use the Simper graphics

capabilities (Section 2), which were identical in power to those of Logo. They

could also begin to learn Logo if they had not already. As in the first

experiment, most students did not complete both curricula, so things like

"pushdown stacks" were discussed only in terms of special projects which a few

students undertook.

Part 2 of the new Logo curriculum was changed in the same way as was

Simper Part 2. Part 3 kept the old discussions of literals and simple, direct

commands, but then led into procedures as program elements, rather than·

naming (e.g., with 'MAKE'). Time- and date-telling procedures were the focus

because experiment-l students had generated these on their own and had found

them useful as well as instructive. The idea that problem solutions could be

broken into logical parts was demonstrated simply by a procedure that. called

both the time and date procedures.

Logo Part 4 discussed naming first in terms of procedure names and then

in terms of input variables to procedures. 'MAKE' was only introduced when a

student's special project absolutely demanded it. Execution control was

illustrated in terms of a procedure that called itself unconditionally, running

forever. This was parallel to what had been done in Simper. Editing

commands were reviewed, and message passing and context were developed in

terms of procedure inputs. Block diagrams, which had little success in the first

experiment, were simplified and given a second chance as aids. As for Simper,

the introduction of functions was unchanged. Logo's parsing of complicated

command-lines was depicted with diagrams, and a fill-in-the-blanks...script.

adapted from the original curriculum.

Logo Part 5 opened with decision-making as an essential ability of any true

computer and a brief discussion of the programmer's role in using such abilities

for his or her purposes. The various Logo predicates were covered using block

diagrams, examples and exercises taken from the original curriculum. The part

predicates play in decision-making was emphasized. Composition of commands

was discussed, particularly along the lines of a telephone-call metaphor. This

was expanded further in terms of good program articulation as the following

p~ogram was developed. The use of simple recursion (iteration) and stopping

rules was motivated by a clock simulator which printed "TICK" or "TOCK"

depending upon whether the time (in seconds) maintained by the system was"

even or odd. Applications of Logo's two decision-structures ('IF'... and 'TEST'...)

also were contrasted with this program as:

TO KLOK10 TEST EVENP SECONDS20 IFTRUE PRINT "TICK"30 IFFALSE PRINT "TOCK"40 KLOK

where

TO KLOK10 IF EVENP SECONDS THEN PRINT "TICK"

ELSE PRINT "TOCK"20 KLOK

Page 52

50 IFFALSE QUIZ' :PICK: REQUEST

TO SECONDS10 RETURN BUTLAST BUTFIRST BUTFIRST TIME

and

TO EVENP :X:10 RETURN ZEROP REMAINDER QUOTIENT :X: 2

were also defined by the students. That Logo has, as most languages have,

redundant operations, was demonstrated by having students write a procedure

CAI.N'T') equivalent to 'NOT'.

True recursion (making use of local contexts) was introduced, as in the

earlier curriculum, using the "little brothers" analogy of Brown and Rubinstein.

The true effect of returning control but not a value from a recursively called

instance of a procedure was clarified.

The concept of a "bug" (unforseen error) in a program was illustrated by a

number-gu3ssing-game program similar to that in the Simper curriculum.

Students were asked to design the program and then modify it in several ways,

all of which, except the last (using 'COMPARE'), suffered from particular

inabilities to interact reasonably with the human guesser:

TO QUIZ :PICK: :GUESS:10 TEST COMPARE :PICK: :GUESS:20 IFTRUE PRINT "SMARTY'"30 IFTRUE QUIZ RANDOM REQUEST40 IFFALSE IF LESSP :PICK: :GUESS: THEN PRINT "GUESS LOWER"

ELSE PRINT "GUESS HIGHER"

TO COMPARE :X: :Y:10 IF BOTH NUMBERP :X: NUMBERP :Y: THEN RETURN EQUALP :X: :Y:

ELSE RETURN "FALSE"

Logo's file system was introduced at this point because it seemed natural

that students would want to save this particular program. As had been done

earlier for editing commands, a one-page manual was included for file

manipulations and abbreviations. Some examples gave practice.

Recursive procedures that return values were introduced using a more

thorough treatment of an example from the original curriculum. Both block

and little-brother diagrams were used to describe how a procedure-that removes

all instances of a selected letter from a selected word should work. The

students were asked to try their hands (and heads) at solving the problem by

synthesizing the procedure. Errors and questions were

were provided. A playlike script attempted to solidify

to be noted and solutions(

understanding of one

solution. Different forms of solutions (e.g., left- and right-recursive) were also

discussed. Then a modification was suggested which would lead to the solution

of another problem: writing a procedure to reverse a word. Up to this time,

no stopping rules had been concerned with numerical criteria. Now, counting

and program self-modification were introduced by a procedure that counted up

(or down) to a limit and then modified itself permanently by self-erasure:

TO SELFDESTRUCT :HOWSOON:10 IF LESSP :HOWSOON: 1 THEN ERASE SELFDESTRUCT

ELSE SELFDESTRUCT DIFFERENCE :HOWSOON: 1

The final of Part 5 developed Polya's ideas on solving problems in terms of

the structure of general recursive procedures. Several projects derived from the

first curriculum were presented. Students could then go on to Simper and

graphics, as they pleased.

The graphics curriculum was derived from that presented to students in".groups IV and V (Table X) in the first experiment. Since students in the

second experiment would have already mastered much of the basic languages, it

was shortened (to 7 pages) and concentrated on animation projects. Each

student who completed either or both languages was asked to think of a project

to work on, graphics providing an enjoyable and quite acceptable medium.

What and how the students were taught were functions of two main beliefs:

(a) testing should be an educational experience; and (b) people should

understand as many of the valuable products of their culture as possible.

The nature of the tutoring prescribed implicit testing of each student, yet

all students always got each "answer" eventually. Especially in the second

experiment, students saw their actions precipitate prompt, accurate tutorial

responses. For both th" students and the research, a working goal was to have

students come to feel at ease with dialectical responses to their questions. For

a few students, this proved to be a difficult departure from their accustomed

experiences in formal schooling.

One knows not when a cultural product might be essential (physically or

psychically) to the individual or to the whole culture. But value is subjective

and evanescent, and one who finds an application for a cultural artifact may not

also find others expressing agreement that the application is valuable.

Nevertheless, any successful try at an application (discounting plain luck) first

demands some understanding. This reeks of technology, yet art, history,

engineering and gastronomics all draw from science to form their own

technologies. In short, everyone should understand and be comfortable with his

or her machines (e.g., Pirsig, 1974)--in the particular instance here, the

,"machine's machine": the computer. Some of the children in these experiments

hopefully would benefit in just this way, even if they might not discover the

fact for years. A nagging fear that this might be a vain hope was instilled in

this author when cO'nversing on this research with a successful educational

researcher, who regularly uses computers for statistical analyses. Hearing that

computers can do more than perform numerical computations left that

professional surprised--an example of how a tool can be misunderstood.

------'--.

Page 55

4 Data Acquisition and Analysis

The simple methods chosen for obtaining data and the type of analysis

believed to be appropriate for this essentially qualitative study will be discussed

here. Some reasons why the analysis should not be founded naively upon

classical statistical inference will also be outlined here.

Throughout both experiments, the Simper and Logo interpreters saved

information on each student's activities. Each command or response typed by a

student was appended to his or her individual protocol file on the operating

system's disc-storage. Prompts and error messages elicited from the interpreters,

and output from students' programs were also saved as they happened. Each

such piece of information was tagged with its time of occurrence. At the end

of the first experiment, the Logo and Simper interpreters were modified to

accept these files directly, in place of keyboard input. Each student's

interactions with the interpreters could thus be replayed and be observed in

their proper context. In addition, the error-message and timing data in the

protocol files could be analyzed in more conventional ways by forming summary

statistics such as error frequencies and typing delays (response latencies). This

sort of data was not of particular interest, except insofar as it could be used to

point out particularly common errors, or confusions due to imperfections in the

curricula or the tutoring. Some additional data were obtained from notes made

by the tutors during the first experiment and the author's notes from the

second experiment. The bulk of the data derives from the latter notes and

replays of recorded protocols. Some problems with the IMSSS time-sharing

system, encountered during the first experiment, are discussed in report-l.

Most, of them also affected the second experiment in minor ways."

The usefulness of these experiments rests upon the ability to understand

students as they have tried to learn Logo, Simper and the concepts explained III

· Page 56

the curricula. Classical hypothesis-testing is not of concern in this work,

although others have attempted to reduce their analyses of children learning

programming to clinical forms, e.g.:

"Children who have had a Logo experience for several _semesters will perform significantly better on problem solvingtasks than children who have been in a non-Logo controlenvironment."

-- Folk et alia, (1973).

For this work, the goal has been an exposure of basic features of how

children think in the relatively unconstrained environment of a programming

laboratory. That is a qualitative exercise in careful judgement, and it centers

on a detailed study of errors made by students as they tryout new ideas for

themselves. But, as in any analysis of data, an analysis of errors must be valid

in the sense that its meaning is not warped by analytical constraints.

"It is a capital mistake to theorize before one has data.Insensibly one begins to twist facts to suit theories, instead oftheories to suit facts."

--Sherlock Holmes, by Sir Arthur Conan Doyle.

Whenever statistical procedures (such as classical hypothesis-testing) are

applied to data, certain mathematical assumptions (e.g., of scale and

distribution) about the data must legitimately be met, if resulting conclusions

are to carry any scientific weight. In too many research settings, the

importance of procedural assumptions is ignored, generating technically invalid

or misleading analyses.

These remarks evangelize to those who, perhaps as students or other well-

intentioned researche.rs, might be seduced by the apparent power or elegance of

various, common, analytical procedures (e.g., analysis of variance), while being

unaware of some of their potential for frivolous application to expediently

massaged (e.g., vacuously scaled, "transgenerated" and/or "Windsorized") data.

In the social sciences,especially in education, the style of research too

often reflects a Quixotic quest for numerical results, apparently stemming from

the belief that quantitativeness is a precursor of objectivity and respectability

in one's discipline.

"They use statistics as a drunkard uses lampposts, for supportrather than illumination."

--Andrew Lang.

For instance, some psychologist's fundamentally qualititative data might

mysteriously be provided a "scale" on which important "variables" could be

"measured"--the accrueing benefit to psychology ranking with that brought to

music by some quitarist's chance strumming of the Lost Chord.

Quantitativeness at any cost is a precursor of sham not objectivity. This, and

the dangers lurking in the fog of "cookbook" mastery of statistics, are amplified

by the relatively easy access most researchers now have to computerized,

statistical procedures (e.g., Ellis, 1972). Perhaps as seriously, widespread use of

standardized procedures has led to stereotyped theorizing (e.g., to hypothesis

testing restricted to linear models and Gaussian-distribution theory), wherein

convenient rather than reasonable procedures define the theory, and the implicit

necessary assumptions of the procedures are virtually ignored. The judgemental

analysis for this work hopefully respects the qualitative nature of the data to

which it is applied.

An example taken from Simper protocol data illustrates the nature of the

judgemental analysis used here. It shows how one student suddenly seemed to

grasp a concept with which he had been having trouble--name-value association

(addressing) in Simper. If the p!,ogramming is unclear, the reader should refer

.back to Chapter 2. The student's dialog with Simper is reproduced here as he

was engaged in writing a program to realize the function: x2 - 3 :

003 :2

015 :ASK A016 :STORE A 200017 :MULTIPLY A A018 :SUBTRACT A 3019 :WRITE A020 :RUN 15:

He appears to understand the purpose of addressing in 'STORE A 200', but

his program contains several errors that suggest otherwise. The first causes

execution to stop at 017 because the symbol 'A', used in the address field of the

instruction in 017, has no binding and thus no associated value. The student

thought he could square the A register's content with the instruction:

'MULTIPLY A A', and he thought he could subtract 3 from that with:

'SUBTRACT A 3'. In both cases, the meaning of the register field seems to be

understood, but the address field is misunderstood. The student corrects the

first error (messages from the interpreter are in lower-case):

020 :FIX 17017 :MULTIPLY 200 200200 isn't a register, use a J b, or p017 :MULTIPLY A 200020 :RUN 15:

and the program works except that, because location 3 contains the value 2, the

subtraction doesn't do what he expected. At this point he seems to understand

that he can store and access values via addresses (names) because of his correct

use of the register and address fields of the 'STORE' and 'SUBTRACT'

instructions. But the idea crystallizes:

020 :FIX 201201 :3

when he associates the desired value 3 with the name (location) 201,-.

020 :FIX 18018 :SUBTRACT A 201

and correctly accesses it to complete his program. From this dialog, one can see

the student begin to apply the concept in correct fashion (in the 'STORE'

instruction), then fail because he has not yet mastered it fully, and finally

succeed, partly helped by simple error diagnostics. The student later made a

similar mistake, but corrected it at once.

For the purposes of these experiments, this type of analysis can suggest

when and how a student masters something presented in the curricula. Students

can be compared in far greater detail than can be done with occasional discrete

tests, the curricula and languages may be evaluated very finely, and the

preliminary aptitude test's validity may be rated subjectively.

The language evaluation aspect of the protocol analysis is partly

demonstrated by the following examples from Logo and Simper protocols of

absurd or misleading responses to students' syntactic errors. First, consider:

..PRINT :::SNOOPY:::don't use the empty thing for a name

in which the student's obvious attempt at multiple indirect-addressing is

completely misconstrued by Logo's simplistic parsing (the first pair of colons

are found to contain no name string). And second:

001 :SUBTRACT 1 FROM P002 :RUNwarning! you forgot to name a location frompillegal memory reference 0 at 1

in which Simper, striving to extract three fields and no more from the student's

line, compressed a simple syntactic error and generated a more advanced type of

error. Not only was this spurious error unrelated to what the student had"

done, it exposed the student to a situation for which he was not yet prepared

(Le., the use of assembler symbols). These examples were taken from the first

experiment's data. Since it was in part a pilot study for the second, the

analysis led to changes in Logo and Simper that corrected at least some of these

kinds of faults.

It should be clear that the Logo and Sirnper interpreters used are not

"smart". They do not tutor their users on the semantics of programs--in the

experiments, that was left to humans. The interpreters do little more than trap

syntactic errors, sometimes acceptably well:

001 :SHIFTunspecified register, use a, h, or p001 :SHIFT 7676 isn't a register, use a, b, or p001 :SHIFT Ashift uses 1, or r or @ and a number in the address field001 :SHIFT @56@56 isn't a register, use a, b J or p00 1 :SHIFT L 56I isn't a register, use a, b, or p001 :SHIFT A L57

As was mentioned earlier, a simple analysis of the protocol files was also

carried out. For example, if a Simper student's errors were categorized and

plotted as in the graph in Figure 11, an interesting effect usually could be

observed: familiarization with the language led to a decrease in errors classed

as syntactic and an increase in those classed as semantic--an infererence being

that as students increase their active programming vocabulary, they can more

easily realize their ideas about problems as programs and find that their ideas

(now programs) aren't always debugged. But this is more reasonably

corroborated by tutorial data and detailed protocol analysis.

The tutoring process often was dialectical, especially when students became

confused. It therefore possessed an analytical facet which influenced the

recorded data. For example, when students expressed doubt about their ability

to solve a particular problem, they were asked to explain the solution they had

attempted, then they and the tutor examined the pros and cons of this in

relation to the problem statement, converging toward a working solution. For

billl63.dta;3 AUGUST 1. 1973 12:20PM

1 DAYS. I LOGINS. 33.40 MINUTES ON, 372 KEYS TYPED ON 60 LINES.

RESPONSE DELAY. MEAN & DEVIATION: 32.15 34.35 SEC,

1.00 LOGINS/DAY. 33.40 MINUTES/DAY. 372.00 KEYS/DAY

33.40 MINUTES/LOGIN. 372.00 KEYS/LOGIN. 60,00 LINES/LOGIN

11.14 KEYS/MINUTE. 6.20 KEYS/LINE. 1.80 LINES/MINUTE

36 ERRORS: 36 GENERAL. 0 NAME. 0 RUN. 0 FIXUPS

36 SYNTAX ERRORS •• 60 SYNTAX ERRORS/LINE. 1.08 SYNTAX ERRORS/MINUTE

.00 RUN ERRORS/LINE •. 00 RUN ERRORS/MINUTE

Page 61

o 10 2DI I I

11###################21 ##########31##41#61#61#71#81#

30 40 50 60

llUNSPECIFIED REGISTER. USE A, B. OR P21EMPTY ADDRESS FIELD?31SHIFT & ROTATE USE L. R OR @ & A NUMBER IN THE ADDRESS FIELD41EXCHANGE USES A REGISTER IN THE ADDRESS FIELD510NLY VALUES FROM 0 TO 999 MAY BE PUT611SN'T A REGISTER. USE A. B. OR P71SHIFTS OR ROIATES MUST BE BETWEEN -999 & +99981UNKNOWN DPERATION

0.2 +

0.1Errors per

Command Line

I /0\ ·syntactic

I I \r \0 .,, ~I semanticI * . .

o +----+----*----+----+----+----+o I 2 3 4 6 6

Weeks in Course

Fig. 11. A Simple Quantitative Analysis of Protocols.

reasons outlined earlier, this technique was employed extensively and uniformly

only in the second experiment.

Implici t testing was thus an important part of the curricula and tutoring

(e.g. pages 49L & 49S, Appendix 3), apart from the aptitude testing done before

both experiments and after the second. It allows students and their mastery of

the concepts to be compared at varlOUS stages.

The second experiment's post-testing was done only with those students who

completed all curricula and projects for both Logo and Simper. The posttest

contained questions like those used in the preliminary test, but also asked

questions that required writing Logo and Simper programs (see Appendix 2).

The preliminary aptitude test's results were presented as a rank-ordering of

the students (Figure 10) obtained by a "forced-choice" evaluation of their work.

Perhaps this is not justifiable, for a test whose validity remains uncertain. At

least a few students, especially near the medians, might well be reordered or

considered hopelessly tied. Yet rank-ordering enforces transitivity. The theory

behind the test is simple and qualitative: take as questions examples of the

thinking that programmers are typically asked to do, where some types of

thinking are more important, in the programming sense, than others. The

former relates to validity, the latter to transitivity. No part of the theory

suggests cardination or interval scaling. Perhaps a careful, subjective evaluation

of students' constructive answers can more nearly approximate an objective

ranking-technique (if one exists) than falsely objective testing/scoring

procedures can. The theory behind the test may be wrong or incomplete, but

determining that is one purpose of the experiments: what do students'

interactions with the preliminary test have to do with their interactions with

the programming curricula? The test's validity teeters on the subjective choice

of questions, and stands or falls subject to experimental data.

5 Results

Anecdotal and judgemental information will be presented which helps in:

(a) understanding the students, (b) evaluating the tests, programming languages

and curricula, and (c) characterizing relevant features of the tutorial process.

Apart from normally recorded data (replay files and tutorial notes),

students provided both direct and indirect feedback in both experiments by

explicit opinions and by their behavior. Figure 12a summarizes students'

responses to a questionnaire they received shortly after the first experiment.

The total numbers of opinions for all rows are not identical because some

students felt insufficiently exposed to every item to render an opinion. After

the second experiment, a somewhat more qualitative questionnaire was given, but

only to a few students who had finished both curricula and some project. Their

comments appear in Figure 12b.

Most of the feelings expressed in Figure 12 correlate with casual comments

made by the students during the experiments. In the first experiment for

instance, the plotter was preferred to the robot because "it draws better" (it

produced more faithful drawings); the plotter was preferred to Logo graphics

because it produced portable, permanent results; and Logo graphics was

preferred to the robot because it was faster, more accurate, and personally

available for each student. In the second experiment, more emphasis was placed

on the languages and concepts, but most students still expressed clear

preferences for graphics and Logo over teletypewriters and Simper, despite the

addition of full graphics capability to Simper. Graphics instruction in the

second experiment occurred only at the end of either curriculum and was related

to a project chosen lly each student reaching that point. Thus, each student's

liking of graphics and animation was a function of his or her feelings about

the project(s) chosen. For example, one student chose to implement a graphic

Tone of Student Remarks

Subject Negative Noncommittal Positive

Plotter 1 16Graphics Turtle 2 26Games 3 25Tutors 2 3 25Return again 2 3 25Train 3 14Robot Turtle 1 1 9Logo 8 21Logo Lessons 3 8 18Simper Lessons 5 5Simper 3 3 5Teletypewriters 4 12 11

Subjects are ranked on relative fraction of positive remarks.

Fig. 12a. The 1973-Students' Preferences

Page 64

Likes:

"I got to learn two languages and 1 was able to betterunderstand the difference between languages machinesunderstand and languages people understand."

"Liked everything about it and had a great time."

"I liked being able to use letters as well as numbers inwriting programs-- I was able to write programs usingwords and sentences, not just numbers."

"It gave me something to do."

"I liked the experience of getting to know them [Simper &Logo]."

"Everything was A.O.K. including the teacher ..• alwayswilling to help."

"The amount of time [plenty of it] to do things."

"I like the fact that Logo is so easy to follow."

"['The curricula were] well written, ... and 1 feel 1 learnedalot. 1 also think the teacher did a good job."

Dislikes:

"I didn't really learn that much, you would just learnsomething and then forget it. It either was so easy or 1didn't understand it and got boring."

"Simper '" [I can't follow] where it goes next as easily asin Logo." .

Suggestions for Improvement:

"There should be a little bit of discussion for everybodybefore the beginning of each class."

"Have a few review sheets and review 'quizzes'."

"Drop Simper."

Fig. 12b. Some 1974-Students' Opinions

Page 65

ping-pong game complete with scoring (Appendix 4). In doing so he learned

virtually all there was to know about the graphics system and thence rated

using graphics first among his experiences.

The item listed as "games" in Figure 12a refers to certain programs

accessible to students on the IMSSS system, such as Hangman, which were

intentionally not announced until the students completed most of the curricula.

Some students, of course, accidentally discovered a game or two. The policy was

that games could be used after a student's regular session with Logo or Simper.

Features of popular games are mentioned in report-I. Students were encouraged

to write their own games and some were used as examples in the curricula,

particularly in the second experiment (see Appendix 3).

Since, as outlined earlier in Chapter 3, the tutors generally fell short of

expectations in the first experiment, their highly favorable rating in Figure 12a

could provide ammunition for those who believe that students are incapable of

appraising their teachers on educationally relevant grounds. The remarks in

Figure 12b, however, evidence some astute thinking; particularly the first and

third, which are beyond expectations. The student who felt she hadn't learned

much also wanted quizzes and reviews, she was apparently not aware of the

testing implicit in the curricula and needed clearer motivation. Her faint

praise that: "It gave me something to do", also points to a lack of motivation.

Furthermore, she had done some programming in Basic in school and never

truly saw the value of Logo's more general structure. Unfortunately, she

enrolled late and her preliminary feelings aren't available for comparison with

those of others from her school (Figure 13).

One prevalent opinion among students familiar with both Logo and Simper

was that "it's harder to do things in Simper". So most students preferred to

work with Logo, regardless of which language they started with. Figure 14

Th~ School-Teacher's Question:

"1 wish to be ... in the 8-week session of computerprogramming, being offered to junior high students withli ttle or no experience with a computer or computerlanguage. Tell what contacts and interests you have thatprompt you to want to take advantage of this opportunityand to be involved with a computer and computerprogramming for an 8-week session."

The Prospective Students' Responses:

"Computers fascinate me and 1 really would like to learnsome of the ways a computer can be used. 1 have neverused a computer before, but 1 have seen people usingcomputers and programming them."

"1 think it would be interesting to learn the computerlanguage. 1 have used computers before and have enjoyedit very much."

"1 like math and figuring out equations and other thingslike this. 1 have done some work with computers, butnot very much at all, and I haven't done any work withLogo. I would like to have some sort of career dealingwith mathematics, and computer programming would bevery interesting and fulfilling."

"My dad is a student at the ... school and talks aboutcomputers and how they can solve problems. 1 would liketo learn how to use them myself and also be able to talk'computer language' with my dad."

Fig. 13. Some 1974 Students' Preliminary Feelings

Page 67

tabulates the proportion of time that students spent using Logo (and, by

complementation, spent using Simper). Note that, within each group, students

are ordered by pretest rank. Thus Figure 14 may be matched with Figure 10 to

obtain further information. This convention will be observed in other figures

in this section, whenever it is appropriate.

In the first experiment, few students finished the Logo curriculum, so Group I

spent negligible time with Simper (Figure 14a). But many Group II students

went far enough with Simper to be able to start Logo, partly motivated by

seeing their friends' work. In the second experiment, more time and a

somewhat shorter curriculum allowed Group I students to spend some time in

Simper (Figure 14b).

In either experiment, Group II's behavior shows that once students began using

Logo, they stayed with it, almost excluding further work with Simper. Figure

14 also shows that students using Logo and Simper simultaneously (Group III),

subject only to the stricture that Logo and Simper curriculum parts alternated,

chose to spend most of their time with Logo (apart from one, Figure 14b third

from bottom, who nearly excluded Logo work, spending time on a Simper

number-guessing game). Group III answered a capability question: students can

learn two languages, nearly simultaneously, and can do so at least as fast as

students who learn the same languages sequentially.

Mass preference of Logo to Simper was a desirable outcome in terms of the

students' computer literacy. Although Simper provides a convenient way to

learn and experiment with assembly/machine-language programming, it was

hoped that students would see the advantage of a high-level language. Indeed,

Logo offers what many students seem to want: easy access to message and,

picture processing. It offers a computationally more important feature: ease of

phrasing complicated control structures. However, appreciation of this latter

idea was usually confined to the more able students.

(Logo hours I Simper + Logo hours, versus pretest rank,"-" denotes students who took the test but not the course)

Group I

.99 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXx1.0 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX1.0 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX1.0 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX1.0 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

. .98 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX1.0 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX1.0 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX1.0 ·XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX1.0 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX.99 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXx

Group II

.70

.34

.48

.22.

.310.0

.17

0.0.04

0.0

XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXxxxxxxxxxxxxxxxxxiiiiiiiiiiiX~XXXXXXXXXX

XXXXXXXXXXXXXXXx

XXXXXXXXx

xx

Group III

.82 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

.69 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXx

.64 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

.87 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXx

.67 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXx

.69 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXx

.68 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX


.88 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Fig. 14a. :Breakdown of the 1973-Students' Programming Time

(Logo hours I Simper + Logo hours, versus pretest rank)

Group I

.83 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXx'.92 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX.84 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX.80 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

1.0 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX1.0 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Group II

.32 XXXXXXXXXXXXXXXX

.58 XXXXXXXXXXXXXXXXXXXXXXXXXXXXX

.61 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXx

.18' XXXXXXXXX

.01 x

Group III

.86 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX


.82 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

.13 XXXXXXx

.71 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXx

.63 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXx

Fig. 14b. Breakdown of the 1974-Students' Programming Time

Before further discussing the students' behavior, something can be said

about the validity of the preliminary test. For Group II, Figures 14a and 14b

indicate a strong correlation between students' ranks on the pretest and the

time they needed to complete the bulk of the Simper curriculum--Pearson

(Kendall) correlations of .9 (.8) and .6 (.4) respectively, the latter reduced from

.9 (.7) because the first student could not stay in the experiment long enough.

Students were also ranked subjectively according to final programming ability

and dedication to the tasks presented to them in the curricula. Figures 15 and

16 show these ratings, again by pretest rank, for all students.

For the first experiment, Figure 15a also tabulates the mean rate of errors

in each student's commands throughout his or her work with Simper. Some

slight, joint trend of error rate and pretest rank seems evident. However,

averaging errors in this way blurs the nature and importance of individual

errors. Without referring to detailed protocol analysis, such a correlation

merits little more than a "that's nice". For example, typing and reading ability

varied greatly among the students. Furthermore, some students forged along,

not caring how many errors they made, while others worried inordinately about

making mistakes, particularly observed ones. Various combinations of such

abili ties and attitudes obviously can confuse simple comparisons of error rates.

It happens that the fourth-ranked student (Figure 15a, with a high error-rate)

feU into the "unbridled typist" category; the third and fourth from the bottom

(with low error-rates) were extremely careful, tending to work out commands on

paper before typing them; and the fifth from the bottom had a penchant for

typing random numerals, which never appeared as errors because Simper was

perfectly happy to store them away. Apparently anomalous error-rates often

had explanations that bore directly upon correlations of pretest rank and error

rate.

Examining the "mastery" and "perseverance" columns of Figure 15a, we also

Groups II and III (Simper data)

("-" denotes students who worked less than 3 hours)

Rankings Based Upon SubjectiveEvaluation of Performance

Errors per Command Mastery Perseverance

.06 XXX 1 3

.14 XXXXXX 3 2

.11 XXXXx 3 3

.26 XXXXXXXXXXXX 4 3

.03 x 2 1

.07 XXx 3 2

.07 XXX 2 1

.16 XXXXXXX 4 1

.34 XXXXXXXXXXXXXXXX 5 4

.23 XXXXXXXXXXx 4 4


.50 XXXXXXXXXXXXXXXXXXXXXXXX 5 5


.15 XXXXXXx 6 5

.13 XXXXXXx 6 2..16 XXXXXXXX 5 4

.34 XXXXXXXXXXXXXXXXX 5 4

.27 XXXXXXXXXXXXXx 6 3

Fig. 15a. 1973 Simper Students' Performance Versus Pretest Rank

Groups I and III (Logo data)

("-" denotes students who worked less than 3 hours)

Rankings Based Upon SubjectiveEvaluation of Performance


.16 XXXXXXXX 1 1

.13 XXXXXXx 2 1

.28 XXXXXXXXXXXXXX 2 1

.33 XXXXXXXXXXXXXXXXx 3 2

.32 XXXXXXXXXXXXXXXX 2 2

.35 XXXXXXXXXXXXXXXXXx 4 5

.22 XXXXXXXXXXX 5 5

.26 XXXXXXXXXXXXX 6 5

.21 XXXXXXXXXXx 2 1

.16 XXXXXXXX 4 4

.15 XXXXXXXx 5 3




.19 XXXXXXXXXx 3 2

.28 XXXXXXXXXXXXXX 5 4

.17 XXXXXXXXx 5 3,29 XXXXXXXXXXXXXXx 3 2.15 XXXXXXXx 4 2

Fig. 15b. 1973 Logo Students' Performance Versus Pretest Rank

("_If denotes students who worked less than 3 hours)

Rankings Based Upon -SubjectiveEvaluation of Performance


Groups II and III (Simper data)

.08 XXXX 2 2

.08 XXXX 2 2

.20 XXXXXXXXXX 1 2

.07 XXXx 1 1

.04 XX 1 1

.04 XX 2 3

.04 XX 1 1

.09 XXXXx 2 2

.09 XXXXx 2 3

.05 XXx 3 1

.07 XXXx 3 2

Groups I and III (Logo data)

.23 XXXXXXXXXXXx 1 1

.12 XXXXXX 1 1

.19 XXXXXXXXXx 2 2

.14 XXXXXXX 1 1

.23 XXXXXXXXXXXx 2 1

.09 XXXXx 1 1

.21 XXXXXXXXXXx 3 3

.19 XXXXXXXXXx 2 1

.20 XXXXXXXXXX 3 2

.20 XXXXXXXXXX 3 3

Fig, 16. 1974 Students' Performance Versus Pretest Rank

Page 74

see some mutual trends with pretest rank. High rankers, especially in mastery,

tend to be above the median; low rankers below. Figure I5b shows similar

results for Logo students. Note, however, the lack of obvious mutual trend

between error rate and rank in Figure I5b.

Protocols provide the following explanations. In Groups I and III: the

unbridled typist returns with a friend as the fourth-and fifth-ranked students;

careful planners are bottom and third from the bottom; the random-numeral

typer is now caught by Logo, generating a higher rate, sixth from the bottom;

and a new phenomenon: picture-printers, fifth, tenth and eleventh from the

bottom, who discovered how 'PRINT' commands could be employed in procedures

that "drew" their favorite things (like the "Starship Enterprise"). The latter

three students made relatively fewer errors because they stagnated at this point

in the curriculum. Students were never coerced to continue the curriculum.

Rather, a wait-and-see attitude was adopted, hoping that stragglers would

eventually notice" that other things, being done by other students, could also be

interesting. This tack failed with one of these three students from the first

experiment.

In the second experiment (Figure 16), there is again little common trend

between error-rate and pretest rank. But again, from protocols, notable

exceptions can be explained. For instance, the third student with Simper data

has a high error-rate because more than half of all his errors were made

playfully, in response to a naming error-message he received one day when he

tried to save a program under an illegal name. The middle Logo student has a

very low rate because he authored several games (notably graphics ping-pong)

which he and others used a great deal, and with little chance for error. As in

the first experiment, test rank and subjective evaluations are correlated

somewhat.

In general, students experimented more with Logo than they did with

Simper, apparently because they felt more able to express their ideas in Logo.

This partially explains why the median error-rates in the two experiments for

Logo students (.24 and .20) are higher than those for Simper students (.16 and

.07). An additional cause is simply that one has a wider variety of errors to

commit in a Logo command. This had more noticeable effect in the second

experiment (Figure 16). The lower overall error-rate of students in the second

experiment also correlates with their apparently better performance· on the

preliminary test (compare proportions above performance breaks in Figures lOa

and lOb). More prompt and accurate tutoring also tended to reduce the total of

errors.

Understanding the Students. Here the central interest is, of course, the

processes through which students learn programming. The goal being to find

observations that shed light on student/tutor interactions in general. The

following results derive primarily from detailed protocol analysis, and begin

with a sampling of the students' initial, unfettered expectations about computers

as expressed first to Simper:

HELLO WHAT'S NEW? DO YOU WANT TO PLAY JOTTO?

DO YOU LIKE SUMMER? I AM FUNNY

THIS TYPEWRITER IS TOO SLOW SOME DOGS ARE WHITE

WHAT IS I2X12? HOW DO YOU WORK?

TEACH ME HOW TO DO A PROGRAM HOW DO YOU KNOW?

THERE ARE TWO MILLION FLYS IN AMERICA LET N = G

YOU ARE WEIRD, BUT SMART MY NAME IS ...

CAN YOU READ AND WRITE? CAN YOU TALK?

THE MAN IS CROSSING THE STREET ARE YOU A COMPUTER?

TO BE OR NOT TO BE PRINT MY NAME

DEAR JUDY, THIS COMPUTER CLASS IS A LOT OF FUN.EVERY ONCE IN A WHILE THE COMPUTER GOES WACKEYI

then to Logo (some error messages are shown--in lower case):

HOW MANY QUESTIONS CAN YOU ANSWER?

HOW MANY WORDS DO YOU KNOW?

COMPUTERS ARE DUMBcomputers needs a· meaningCOMPUTERS ARE ILLOGICAL

HOW LONG HAVE YOU BEEN IN SERVICE?how needs a meaningYESyes needs a meaningAFFIRMATIVEaffirmative needs a meaningYES MEANS AGREED, CORRECTyes needs a meaningI JUST GAVE YOU A MEANINGi needs a meaningI MEANS #176i needs a meaningI GIVE UP

ARE YOU A LOGO OR A COMPUTEn?

I HAVE HOMEWORK TODAY,I HATE HOMEWORK

WHY ARE YOU A COMPUTER?

THIS IS GOING TO BE VERY FUNthis needs a meaningIT MEANS IT WILL BE ENJOYABLE

MY DOG IS BLACK

THE SUNSET IS BEAUTIFUL

PLAY CHESSplay needs a meaningPLAY MEANS TO DO SOMETHING

FUNfun needs a meaningIT'S LOGO

ADD TWO AND FOUR

GIVE ME AN INTRODUCTION

I AM A VERY BADLY GOOD BOY

I AM IN A VERY GOOD COMPUTER CLASS BECAUSE IT IS A PLEASUREWORKING WITH THE COMPUTER, SHE, LOGO, RETYPES WHATEVER YOU WANT

Of course, students had been encouraged to plumb Logo's and Simper's

"minds", and all the above efforts received replies of no more than either

"unknown operation xxx" from Simper or "xxx needs a meaning" from Logo.

Interestingly, Logo's mOre understandable response tended to stimulate dialogs.

Some students struck fortuitously upon primitive operations--Simper:

COMPUTERS ARE FUNNY'are' isn't a register, use 3, h, or pCOMMAND YOU'you' isn't a register, use a, b, or p

('COM' is short for Simper's 'COMPARE' operation), and Logo:

WHERE IS GERMANY?you are not using the trainYES I AM

RETURN YOUR LIBRARY BOOKS NOWyour needs a meaning

GET GOLFsomething missing for getGET GAMEsomething missing for getGET PLAYsomething missing for get

·',Page 78

YOU ARE A STUPID COMPUTERPRINT ••"•DO GO GOgo needs a meaning

MAKE A SNOOPYa needs a meaning

BREAK IT UP; YOU NASTY THING!break

IS THE COMPUTER A COMPUTER?the needs a meaningIS GEORGE HOMSY A COMPUTER?george needs a meaningIS MR. HOMSY A COMPUTER?mr. needs a meaningIS HOMSY A COMPUTER?homsy needs a meaningSHUT YOUR TERMINAL UP ANDGIVE ME AN ANSWER

At this early stage, accidental discoveries of this sort usually passed

unnoticed. Eventually most students did take notice of and exploited various

syntactic features like mindless error-messages, Simper's abbreviation-by-

truncation, and the commenting character ';'--Simper:

UNKNOWN OPERATIONunknown operation unknown

WRINKLE AHALLUCINATIONS

YOU CAN'T TALK WITH ME BECAUSE YOU ARE DUMB

('WRI' or 'HAL' select Simper's 'WRITE' or 'HALT' operations) and Logo:

I AM THE TURTLEi needs a meaning

THISCOMPUTERthiscomputer needs a meaning

PRINT REQUEST* IF PAUL IS GREAT TYPE THIS SENTENCE OVER WORD FOR WORD

PRINT "I DO NOT KNOW HOW TO PRINT"i do not know how to print; YOU LIED

IF OREN IS DUMB, TYPE IF NEEDS A MEANINGoren needs a meaning

Paradox and prediction were favorite techniques that some students used to

"insult" their friends. To his lasting surprise, the latter above student's

trickery hoisted him on his own petard. These were healthy interactions

because students were encouraged to keep experimentation as one of their basic

learning tools.

Initially, these naive programmers often had a very high opinion of

computational technology. It was easy to show them that English is not yet a

mode of communication between human and machine, but it often took a while

for the implications of this to penetrate. At times, students' attempts at

communication were tied to curriculum ideas:

REMARK LITERALLY PUT A BUG IN A

SIMPER COMMANDS ARE FAMILIAR TO COMPUTERS LIKE SIMPER

PRINT "HOWCOMELOGOWORDSDONOTHAVESPACES?"

WILL YOU WRITE ME SOME SIMPER PLEASE

3 4 10 ARE RELATIVE TO THE NUMBERS 15, 17, 29.IN WHAT WAY THOUGH?unknown operation 33 (THREE) IS A NUMBER AND ALL COMPUTERS LIKE YOU SHOULDKNOW WHAT IT MEANS!

Sometimes they became confused about curriculum instructions for giving

commands. The following shows some examples along with the motivating

curriculum excerpt:

A FEW WORDS

LINEFEED

1 TYPING 1

GO TO THE SUPERMARKETBUY EGGS AND BACON

FIX PUT P 2 TO P 1 RUN

... type a few words and ...

... all you do is type LINEFEED and •.•

... and then typing 1 and ENTER ...

(see Appendix 3, page l8L or 17S)

... use FIX to change ... from PUT P 2to PUT P 1 and then use RUN and ...

In fact, some students typed Simper's prompt because it had been shown at the

beginning of a line they were asked to type:

001: ADD A 12unknown operation 001:

One student tried to get a program to run by simulating Simper's runtime

message:

EXECUTING 1 TO 250unknown operation executing

producing an enjoyably idiotic response. Another student, in his frustration,

uncovered a bug; not in one of the interpreters, but in the Sail compiler's

string runtime-routines:

,YOU STUPID COMPUTER'stupid' isn't a register use a, b, or p

The bug disguised the "," and thus the proper error: "unknown operation ,you",

Once in a while, unrestrained joy of accomplishment in solving a problem would

surface, only to be muted by an unbending parser:

YAHOO! I DID IT!unknown operation yahoo!; I KNOW I KNOW

Obviously this student already knew how to protect her comments.

Confusions sometimes arose when students worked with both Logo and

Simper (as did Group III). Logo commands cropped up in Simper protocols and

vice-versa. In these cases, however, the first or second error message usually

was sufficient to remind the student of which interpreter was listening to his

or her typing. In a few cases, students thought they could resort to Logo

commands when their Simper programs failed to produce results. This was one

simple way students gave evidence of being more at ease with the Logo

language. By far the most common interjection of Logo commands into Simper

protocols was in saving programs. Apparently, learning the more complicated

Logo scheme of lientries" in "filesll overrode some students' knowledge of

Simper's simpler filing method.

At the very least, most students initially thought that a computer could

help them on a personal basis:

PRINT "ALL THE COURSES AND LESSONS YOU HAVE TO OFFER"

Agreed; that should, and perhaps will, someday be the case. Several students

discovered Simper's '?' (or 'HELP') command which printed a general description

of the Simper language. While this was never intended to be a necessary part

of the course, it nonetheless was exercised frequently by a few students.

Curiousity and an open desire for aid were attitudes to be exploited and

encouraged. Students' were willing to experiment in trying to use Logo· and

Simper as information resources to help them work on ideas from the

curriculum.

Now, in discussing details of how students learned the concepts and the

languages, the Simper and Logo protocol data will be treated separately. Some

observations relating students' performance and their work on the preliminary

test will also be mentioned.

Simper. Since work with numbers was so much a part of these students'

prior schooling, it was relatively easy for them to accept that a machine

(Sim'per) could have a good memory for numerals. But several had difficulty

understanding that some numerals could have special meaning, other than

counting, to a machine. In the first experiment, this was a problem because of

the premature introduction of assembly language, thus working downward from

English rather than upward from machine language. The latter sequence was

adopted in the second experiment and reduced the incidence of syntactic errors

such as multiple instructions per line, making it clearer that only three fields

can be assembled into one memory cell's machine-language numeral.

,The orderly execution of numerals as instructions was still more abstract.

The shopping-list example (Appendix 3, page 17S) and the house-to-house

collection (Appendix 3, page 31S) failed to motivate successor execution for

some students.. Programs were written with interspersed "holes", despite the

obviously sequential relationship between instructions on either side of a hole.

A self-destructing program used in the first experiment helped here (see report-

1), and in the second experiment, greater care in introducing machine language

seemed to be sufficient. Some of the "holey" programming can be traced to

Group III students who learned to use Logo line-numbers in canonically sparse

(10-20-30...) sequence and hoped the same editing advantages would accrue in

Simper.

In both experiments, addressing values rather than stating them directly

was difficult for many students. One wrote his own time-telling program, knew

what had to be done to get minutes from seconds, knew something about

addressing already, but typed:

001 :TIME A002 :DIVIDE A 60

though he did not intend to divide by the content of location 60. The

curriculum section On indirect addressing was very helpful to those students

who still had trouble with this concept. Not surprisingly, students who had

trouble with the implicit name-value associations of the numbers-in-boxes

problem on the preliminary test also had trouble with addressing in Simper.

The most pervasive problem was mastering the concept of context (or

locality of information) both from the student's point of view as a user and

from the point of view of instructions within his or her programs. The most

common example of the former occurred when a student ran a program and

decided that it needed modification. While it was still running, and perhaps

waiting for an input (for 'CASK' or 'ASK'), he or she would type an editing

command (e.g., 'LIST' or 'SCRATCH'), fully expecting it to be obeyed. This

runtimeledi t-time confusion was seen in every student's work at least once.

Context errors wi thin programs centered upon redundant or memory-

tlclobbering lt sets of instructions. For instance:

001 :PUT B 1002 :STORE BONE003 :ASK A004 :PUT B 1005 ,STORE BONE

or

001 ,PUT B 1002 :STORE BONE003 :ASK B004 ,STORE B @A005 ,PUT P .-3

Page 83

In the first program, the contents of register B and cell 'ONE' are unnecessarily

reset at 004 and 005; in the second, the content of cell 'ONE' is continually

destroyed by 'PUT P .-3' (instead of 'PUT P .-2'). This latter kind of bug was

common, yet it had already been exploited as an example within the curriculum

for the first experiment. It was apparent that a much more explicit treatment

of computational context was needed, and this was done in the second

experiment, with mixed results. Students who had the most trouble with the

candy-machine problem on the pretest typically had the most trouble organizing

their Simper programs.

The most subtle way in which context affected the students was in the

relationships among the interpreter, the assembler and the machine. Most

students in the first experiment didn't fully grasp the distinction between

editing commands and assembler/machine instructions. Sometimes they

attempted to abbreviate the former (e.g., "SCR" for 'SCRATCH') and expect the

latter to be obeyed at once. The second experiment's curriculum was modified

to clarify these issues, which were founded primarily upon the confusion of

editing time with execution time. Its better tack of introducing machine

language before assembly language helped a great deal and explicit discussions

of runtime/edit-time were included. No one question on the preHminary test

seemed to relate strongly to this type of error. This is probably one point for.

improvement of the test.

Toward the end of the curriculum and in student projects, procedures and

their calling sequences provided examples of how programs could be structured

by writing functionally related subunits. In this case, holes were ok. Success

here demanded that the student had mastered the concepts of addressing and

program control. Failures to structure these programs correctly were of two

forms: failure to define a proper calling sequence, and misplacement of the

calling sequence in the flow of the program. Some inputs to procedures,

particularly the return address, were overlooked; once the call itself was

incorporated as part of the procedure body.

Because, in the first experiment, no students had time to do significant

work on the final part of the curriculum dealing with stacks and recursive

procedures, the second experiment treated these programming techniques only as

tools for use in projects chosen by students who had completed the formal

curriculum. When these tools were exercised, by a few students, the notion of

context could be be motivated very well. However, in either experiment, few

students completed the curriculum and fewer still completed some project. In

passing through the course, the data gradually becomes dominated by the work

of the more able, typically older, students. The remaining students simply did

not proceed as far. This has undoubtedly colored later observations.

Before dealing with individual student performance, a few miscellaneous

comments remain. Some students actively exploited features of the Simper

interpreter--for instance, truncation of operation names (e.g., 'STOP' for

'STORE' and 'LOAN' for 'LOAD'). One student occasionally harassed the

machine by repeatedly saving a program on a file that already existed just so

he could respond "no" to Simper's warning: "a program called xxx already

exists! ok to destroy it?". The importance of clear, relevant error messages

also became apparent (see Chapter 4 for examples). An example follows that

shows how misreading one word can dangerously alter the meaning of a message:

SAVEwhat do you want to name your program? YESok, yes is saved

illustrates the care that must be applied to apparently trivial aspects of an

interpreter. In line with earlier comments about contextual errors, it should be

mentioned that the above question and the students together produced several

saved programs called 'SCRATCH'.

Figure 17 displays the sequence in which Simper-related concepts were

learned by each of the students in the second experiment, for which the best

data exists. The time at which mastery occurred was judged as outlined in

Chapter 4, using error analysis. These language-related concepts connect with

one or more of the general concepts outlined in Table I, and so give an

approximate idea of the sequence of their mastery.

Logo. Students were less able to adjust to Logo's string manipulations than

to its more familiar numerical notation. For example, most students had

trouble remembering to quote nonnumerical strings. Logo does not require that

numerals be quoted, but demands that literal words and sentences be quoted.

The former default tended to be generalized by some to their designation of the

latter, especially in direct commands. The second experiment attempted to

clarify these notational matters, but was not entirely successful--all literals

should probably be quoted at first, perhaps even by modifying Logo.

Procedures had not been introduced early enough in the first· experiment, so

those students did not have a framework within which to execute direct

commands and then add them to stored programs by editing. In the second

experiment, procedures were introduced early (Appendix 3, page 18L) and as

being, in essence, new Logo commands. Many students soon caught on to the

value of being able to construct new and personal tools, either for use or

amusement:

TO SKIPIP :0:5 IF ZEROP :0: THEN DONE10 SKIP15 SKIPIP DIFFERENCE :0: 1END

TO WIDL?123 P "DIAJ"124 P "DIAJ NEEDS A MEANING"125 P "OH, O.K."END

I ....__-~.._-_·---"-.-.---

Page 86

Approximate Hours to Apparent Mastery of a Concept

Student (by pretest rank, Figure lOb)

Concept 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Addressing 1.1 3.8 1.2 1.3 1.4 1.2 5.1 1.3 5 1.7 - 2.3 4.1 2.4

Successor .9 1.8 1.3 .9 1 1.2 1.4 1.8 1.6 2.5 .9 .9 1.2 1.7Execution

Simple 3.2 5.6 8.3 2.6 4.7 3.4 . 3.8 2.8 7.5 3.7 4.3 7.7 5.9Control(using 'PUT')

Decisions 3.9 5.8 8.3 3.6 5.9 3.4 2.3 3.3 7.1 3.4 5 7.7 5.9(using 'JUMP'!

'COMPARE')

Iteration 8 8.7 7.2 - 7.3

Sub -Programs - 6.6 6.9 8.2 7.3 9.1 8.5 7 7.8 10.6

Internal .9 1.8 6.7 3 1.6 1.2 2.4 4 9.3 1.8 - 1.5 9.1 1.7Context(using storage)

User Machine 3.2 6.2 8.6 2.5 5.6 1.2 2.4 1.6 7.8 2.4 6.4 5 5.3Context('RUN'-'EDIT')

(Boldface numbers indicate very accurate times, a dash signifies that aconcept was never clearly mastered.)

Fig. 17. Timing of 1974 Students' Mastery of Simper-Related Concepts

TO TRY10 BELLS 9020 P "IF ALEX CANNARA IS YOUR INSTRUCTOR DO NOT I REPEAT DO

NOT COPY SOMEBODY ELSE'S PROCEDURE, OR YOU WILL SPENDTWO HOURS TRYING TO FIGURE IT OUT AND ALSO YOU WILLMAKE ME MAD1!!HWH!!!!!!!!!!!!!!!!!!!!!!!H!!!!!!!"

END

The first above was constructed by a student when, well into the curriculum, he

needed a way of clearing his display screen and didn't know that Logo had such

a command ('CLEAR'). He obviously had already mastered iteration and simple

recursion. Interestingly, simple (last-line) recursion came easily to many

students upon their first exposure to it (Appendix 3, page 20L), and common

ad-libs took the form:

. .. -. -~._--_._._._-_.-

TO RING10 BELL20 RINGEND

TO BICYCLE10 P "LIBBY SHOOP"20 BICYCLEEND

TO TOM10 PRINT "IF TOM WAS NOT GREAT I WOULD STOP WRITING"20 TOMEND

Several procedures (e.g., 'TELLTIME') that were used in the second experiment

were incorporated because students in the first experiment had done them on

their own and thus found them interesting or useful. Sometimes early

procedure-writing attempted the impossible:

TO TELLWEATHER10 PRINT WEATHEREND

In the first experiment, naming (name/value associations) had been

introduced via Logo's 'MAKE' operation, but there was relatively little use for

this in later programming, In the second experiment, procedures were used to

introduce the concept, as named chunks of commands which might even receive

messages or values (inputs) and link them with internal names (Appendix 3,

Logo Part 4). 'MAKE' was never mentioned unless a student's project logically

required it.

Typical errors using 'MAKE' in the first experiment were: (1) forgetting

quotes around name and/or value, (2) using colons around the' name (reasonable

in view of most of Logo's syntax, e.g., 'MAKE :X: "Y'" is really not linking the

value 'Y' to the name 'X', but to the value already associated with 'X'), (3)

inverting name and value positions ('MAKE SUM OF 5 AND 9 ANSWER'), and

(4) linking assignments by one command (a reasonable expectation, e.g., 'MAKE

"SNOOPY" "CHARLIE BROWN" "LINUS''', where the curriculum intended

'MAKE "SNOOPY" "CHARLIE BROWN'" and 'MAKE "CHARLIE BROWN"

"LINUS"').

Naming errors made by students in the second experiment, where procedures

introduced the concept, were reflected by defective input correspondences and

control problems generated during editing. For example: (1) input-variable

names in the title would not match those in the procedure's body, and (2) the

name of a procedure would be edited but not then changed in a recursive call

or a' call in another procedure.

In both experiments, initial confusions about Logo's colon notation (i.e.,

':X:' means "value associated with name 'X"') produced errors like: "PRINT

::SNOOPY::" (to achieve indirect addressing), and: 'RETURN PRODUCT :X: :2:'

or 'DOUBLE :324:' (confusions between literals and names, and between actual

and formal parameters). Part of the confusion arose because Logo does allow

indirect addressing via repeated applications of 'VALUE' ('THING'), and it

allows numerals to be names.

Generally, students who had trouble with the candy-machine and numbers

in-boxes problems on the preliminary test also had trouble with procedure

construction. The concept of context enters at several points in producing a

working Logo procedure and, just as in Simper, is not confined to the

runtime/edit-time dichotomy. One must also consider the context of variables

formed in multiple or recursive procedure calls or in complicated command

lines. The linkage is more subtle in Logo since it is managed by the

parsing/execution stack (see Chapter 2, or report-I), and most students'

misunderstandings showed up as soon as they tried to solve problems requiring

more than one procedure, or even more than one input to one procedure:

TO FUNNYADD :SOMETHING: :SOMETHING:10 RETURN SUM FIRST :SOMETHING: FIRST :SOMETHING:END

The above, when executed, e.g., by 'FUNNYADD 87 15', will not return 9 but 2

instead, because only the last instantiation of ':SOMETHING:' will be on the

execution stack when line 10 is executed.. This student simply thought that the

position of a name in a title line, rather than its character content, linked it

to a command-line input.

The 'DOUBLE' procedure, given as an example which students were to later

modify (Appendix 3, page 28L), provides an exemplary set of errors made by

students early in either experiment. Only the command line and not the title

are shown here:

10 RETURN MULTIPLY oX: 2 10 RETURN PRODUCT :X: :X:

The first is a linguistic confusion: should an operation's name reflect its result

(product) or its action (multiply)? The second is a very common error that

unintentionally makes a squarer--the squaring operation itself being unknown to

most students who made this error!

Since Logo accepts "noise" words such as 'OF' and 'AND' (e.g., 'SUM OF 2

AND 3'), many students expected to be able to use "BY" or "TIMES" in

appropriate places in 'DOUBLE' or its inverse: 'UNDOUBLE'. The pros and

cons of noise words will be discussed later. Examples of personal noise words

and other errors made by students doing 'UNDOUBLE' follow:

UNDOUBLE MEANS TO DIVID

RETURN DIV 2 :NUMBER:

RETURN QUO :NUMBER: :2:

RETURN QUO :NUBER: :NUMBER:

RETURN QUOTIENT :NUMBER: BY 2

Page 90

TO UNDOUBLE IS TO TAKE HALF

TO UNDOUBLE :THING OF :NUMBER:

PRINT DIVIDE :NUMBER: BY 2

PRINT DIVISION :NUMBER: :NUMBER:

PRINT QUOTIENT :NUMBER:DIVIDED BY 2

RETURN QUO OF :NUMBER: AND :NUMBER: BY 2

Some classes of error already discussed appear here, namely English attempts at

solutions, spontaneous noise words, and name/value errors. An additional

problem is evident that concerns the stream of messages processed by Logo

during command execution, namely: to print or return a computed value. Many

students seemed to think that the printing on their terminal was examined by

Logo at the same level as a command. One student believed she needed to

comment (with ';') part of a string because only its first word was a legal Logo

operation:

TO BY10 PRINT "GOODBYE; KAREN. SEE YOU TOMORROW!!"20 GOODBYEEND

Thus students had trouble understanding that the receiver of a message

determines its context and thus its meaning (or effect). Some were

particularly confused and thought that they must, for example, say: 'PRINT

UNDOUBLE 3' even if their 'UNDOUBLE' properly contained a 'PRINT'.

The contrast between 'PRINT' (or 'TYPE') and 'RETURN' was also based

upon the execution-control aspec"t of 'RETURN'--it terminates a procedure when

executed, no matter where it appears. This was typically a problem for some

students, who used multiple 'RETURN's as if they were appending to the output

message, as 'PRINT' does. Typically the several procedures given in the

curriculum as exercises (Appendix 3, Part 4) had all to be done before a

student really seemed to master the basic difference between 'PRINT' and

'RETURN'.

In the first experiment, a problem based upon a preliminary-test question

(the 2-column function-table, Appendix 2, page 128) was presented in both

curricula. Since its command line involved one of the earliest exposures of

students to composition of functions, some attempted solutions are interesting.

It was hoped that students would use their 'DOUBLE' procedure in. the solution:

TO RULE :NUMBER:10 RETURN SUM 9 AND DOUBLE :NUMBER:END

But those not using 'DOUBLE' often became entangled in the mysteries of

nested expressions, noise words and syntax in trying to produce: 'RETURN SUM

:NUMBER: AND SUM OF :NUMBER: AND 9'. Some examples:

RETURN SUM :NUMBER: :NUMBER: 9

RETURN SUM :NUMBER: :NUMBER: SUM OF 9

SUM OF 9 TO THE PRODUCT OF :NUM: BY 2

TO CORRESPOND 3 TO 15, 4 TO 17, AND 10 TO 29

10 MULTIPLY :NUM: BY 220 ADD 9

10 MAKE PROD :NUMBER: AND 2 ANSWER20 RETURN SUM OF ANSWER AND 9

TO ADD :NUMBER:10 RETURN SUM DOUBLE ADD 9

The last example loops forever as 'ADD' calls itself with 9. In the preceding

two examples, students appeared to understand the rule but tried writing the

expression on sequential command lines, among other errors. Such attempts to

communicate values implicitly across command boundaries were initially quite

common and not related to prior work with Simper. In some cases, the

curriculum (Appendix 3, page 18L) was one influence, but most of these

-';.~. .

Page 92

students simply felt it was a natural way to proceed towards a· solution.

misunderstanding of context usually was the culprit.

Again,

Students were always encouraged to decompose a program into a basic set of

related procedures. This was true for graphics projects as well (see report-I).

One problem CSWITCHl3', Appendix 3, page 37L) was quite effective in

demonstrating this principle, particularly in the second experiment because of

the earlier introduction of procedures. Errors in solving this problem and

other, like problems involved coordinating procedure inputs, choosing operations,

and use of the 'RETURN' command. Students who forgot to declare input

names in the title, or used names different from those named in the title,

found that Logo happily supplies them with the default value ...... rather than

complain about an undefined variable. A desirable solution was:

TO SWITCH13 oX:10 RETURN WORD THIRD oX: WORD SECOND oX: WORD FIRST oX:

BUTFIRST BUTFIRST BUTFIRST oX:END

where 'SECOND' and 'THIRD' were previously written by the students to return

the second and third letters of a word respectively. Students often failed to

break the problem into manageable parts and thereby notice that some of the

components had been solved previously. An acceptable solution of that ilk was:

10 RETURN W F BF BF oX: W F BF oX: W F oX: BF BF BF oX:

CBF' abbreviates 'BUTFIRST'; 'F', 'FIRST'; and 'W', 'WORD').

attempts:

10 RETURN W W W F BF BF F BF F BF BF BF oW:

TO SWITCH1310 THIRD :INPUT:20 FIRST :INPUT:30 PUT THIRD FIRST AND FIRST THIRDEND

Actual

The first example shows a common initial belief that one input can be

distributed over several operations. The second shows attempted inter-line

communication, implicit 'RETURN' and English instructions. A related, simpler

procedure, to put the first letter in a word last, was written by one student as:

TO REV :YIP:10 RETURN :IPY:END

In the interesting belief that characters in an input's name map into those of

its value. Because Logo defaults undeclared names, as mentioned earlier, she

persisted wi th this scheme in several procedures, thinking she only had to get

the right combination of letters to succeed.

One frequent error was forgetting to specify all of the inputs in a direct

command or recursive call, especially when that input does not change. One

1973-graphics student defined the following unusual program:

TO STEVE :BD 17 16 48:10 :BD 17 16 48:END

TO BD :L: :A: :1:10 FRONT :L:20 RIGHT :A:30 BD :L: SUM :A: :1: :1:END

She then typed 'STEVE ED 17 16 48', which works (in the sense that 'BD' is

executed), because in attempting to bind the input, Logo runs 'ED' and waits

for a value, which never comes. The student did not seem to realize this,

trying 'STEVE' with a different call to 'ED', with 'STEVE' and 'ED' traced,

would have helped to correct this mistake.

Many students had trouble understanding how procedures communicate

values to one another via 'RETURN'. In the second experiment, for example,

students wrote many procedures that were to return values:

TO COMPARE :SOME: :TOY:10 TEST NUMBERP :SOME: :TOY:20 IFFALSE RETURN "FALSE"30 IFTRUE EQUALP :SOME: :TOY:END

When constants (e.g., "'FALSE"') were to be returned, 'RETURN' was rarely

forgotten, but when another operation/procedure was to be called to generate

the returned value, 'RETURN' was often forgotten or assumed to be implicit, as

in line 30 above. Several students used structures like line 30 to mean: "now

be 'EQUALP' and do what it does"--an attempt to implicitly change a

proced"ure's definition at runtime.

Some projects (e.g., 'BINAR', report-lor Appendix 2, page 127) were taken

from the first experiment's curricula and used as part of a posttest for students

who completed all of the second experiment's curricula. Other projects were

used for the implicit testing process outlined in the tutoring discussions earlier,

and most students added their own, especially when they were able to use the

graphics system. Some are mentioned in report-I. In the second experiment,

for instance, one student designed a simulation of the PONG(R) game and

another began an animated cookbook that was supposed to implement a recipe

visually by allowing the user to manipulate snapshots of spoons, cups, etc.

Some of these projects are documented in Appendix 4.

As done earlier for Simper (Figure 17), Figure 18 displays the apparent

sequence in which Logo-related concepts were learned by each of the students in

the second experiment, for which the best data exists. A few students' work

will be discussed in detail after some remarks about the languages and

curricula.

Approximate Hours to Apparent Mastery of Concept

Student (by pretest rank, Figure lOb)

Concept 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Literal 1.8 1.7 1.1 1.2 1 1.4 1.7 4.2 .4 .5 1.9 .4 1 , .5 .6 3.3Values

Named 4.2 5.6 5.6 2.3 3 2 4.610 4 2 6.1 3.1 - 4.4Values

Command 4.2 2.3 5.6 4.5 3.2 2.8 4.611.4 4.9 6.4 7.1 7.5 - 6.8Parity

Simple 2.7 2.3 1.7 1.3 1.5 1.4 2.8 4.1 4.4 2.6 1.4 ·1.8 10.2 - 6.8Control(sub-procedure)

Simple 4.2 6.5 9.4 7.8 4.8 2.9 5.5 11.4 4 7.8 6.4 9.1 - 6.8'RETURN'

Recursive 15.4 18.9 15.5 17.6 7.9 - - 16.5 28.1'RETURN'(context)

Decisions 7.5 10.1 9.4 7.8 8.5 12.4 26.2 9.5 10.7 - 6.8('IF'/'TEST')

Stopping 11.6 18.1 17.1 11.4 15.2 7.9 - - 11.4 28.1Rules(iteration)

User/ 3.2 2.3 5.6 1.2 4.8 1.i 2.1 3.6 1.8 7.8 1.4 2 2.6 - 1.6MachineContext

(Boldface numbers indicate very accurate times, a dash signifies that aconcept was never clearly mastered.)

Fig. 18. Timing of 1974 Students' Mastery of Logo-Related Concepts

Evaluation of Simper and Logo

As a result of the experiments, various modifications were made or should

be made to the languages.

Simper. First targets for change have been obvious bugs and

inconsistencies iIi command evaluation and assembly. For example, after the

first experiment, 'SCRATCH' was modified to accept the general form for an

address-range specification (e.g., 'SCRATCH 6:8' has the obvious effect). 'SAVE'

and 'GET' were made to accept the name of the file as an input (e.g., 'SAVE

GLOP'), resorting to dialog only when such an input is lacking. A more subtle

change was made to 'SLIDE'. One student was frustrated when his memory

space was effectively exhausted even though numerous holes existed between

program segments. So, by the second experiment, a forward 'SLIDE' (e.g.,

'SLIDE 100:200') could recursively squeeze· out such holes to make formerly

impa'ssible relocations possible. The user is informed of which holes disappear.

In the interest of making the name fit the action and to reduce confusions with

Logo, 'FIX' was replaced by 'EDIT'.

The first experiment also suggested some new operations and a new

command. 'LEXOR' gives a decimal version of "exclusive or" (Table II),

'ERROR' tests a flag set by arithmetic. overflows, 'lOT' communicates with the

Graphics program and the plotter, and 'NEWS' gets the system time schedule

and any new information about Simper (or Logo). 'DIVIDE' was modified to set

the 'ERROR' flag on division by zero, instead of the previous and unusual skip

if-successful convention. The structure of the Simper machine itself was

modified. Five-hundred memory cells and four registers (Le., A, B, C and P)

were made standard (with upper limits as shown in Figure 2). This was

motivated by students suggesting projects for which 250 memory cells were

insufficient. The additional register was added to make procedure calls more

convenient, especially via a student-programmed stack. The changes were

achieved by a generalized restructuring of the interpreter.

After the second experiment, more changes were made, mostly on

suggestions of students (see Table III). Significantly, the students were more

concerned with improving Simper's editing abilities (e.g., by adding 'FLIP') than

with adding new powers to the simulated machine.

Recommendations. Changes are relatively easy to make in Simper because

it is written in a high-level language. An important improvement would be the

simulation of a micro-coded machine with interrupt handling, so that students

could be exposed to some aspects of modern machines. Simulated devices other

than the turtle (e.g., a disc) could also be pedagogically beneficial. However,

too many "features" can be detrimental. Since a valuable computational idea is

that problem solutions can be broken logically into parts that are in turn

realized by certain basic and sufficient abilities of some machine, the abilities

chosen should nof individually be too powerful. A pedagogically useful addition

would be the ability to run the machine backwards as well as forwards thus to

allow partially undoing a computation.

Perhaps the most beneficial results would be achieved by making the

interpreter smarter and more congenial in terms of its responses to naive

programmers. A first step would be a structured treatment of the '?' or 'HELP'

command. Successive applications of this command in, say, an address field

would obtain successively more detailed help about address fields. In this

respect, the interpreter would be more knowledgeable about itself. More general

(and more difficult) powers, such as the ability to evaluate programs, would be

of obvious value in counselling students.

Logo. In the present version of IMSSS Logo (excepting Sailogo),

substantial changes are typically difficult to make. For this type of work, the

interpreter should have been written in a high-level language (e.g., Manis,

1973). Several changes in commands, apart from addition of animation, were

made after the experiments (Table IV). Consistency and clarity of nomenclature

was the goal. For instance, some Logo predicates mark themselves as such by

employing the suffix "P" (e.g., 'LESSP') and some do not (e.g., 'IS'). This was a

source of confusion for a few students. 'IS', in particular, is also very

suggestive of wrong i~terpretations (e.g., the line "TEST IS :X: LESSP 0" should

be 'TEST LESSP :X: 0'). Thus 'SAMEP' was introduced as an alternative to

'IS'.

'Recommendations. Operation names should name the action (e.g., 'ADD')

rather than the result (e.g., 'SUM')--or, as the precocious 9-year-old put it: "I'd

make a whole new language without any weird commands like 'PRODUCT' and

'REMAINDER'. I'd have MULTIPLY and FINDREMAINDER.". Predicates,

rather than simply being suffixed with "P" should end/start with "?" (e.g.,

'LESS?'). If ':X:' is to be analogous to 'VALUE "X"', then nesting of colons

should be allowed. Additionally, a different symbol should be used instead of

colon to delimit place holders in procedure ti ties, or a different, nestable

synonym 'for 'VALUE' could be chosen (e.g., "@"). Numerals should be

disallowed as names or always be quoted when used as literals just as text is.

More fundamentally, value names and procedure names should u.se the same

dictionary and notation (e.g., 'A' could either stand for 'VALUE "A'" or call

procedure 'A', as in Algol 60). Pedagogically speaking, any distinctions of

program from data should be defined by the student and not be automatic, and

pronomial notation seems most natural.

Another fundamental point concerns command evaluation. Commands for

editing, erasing, listing and filing currently quote rather than evaluate their

inputs (i.e., 'EDIT ROCKET' instead of 'EDIT "ROCKET'" thus disallowing

'EDIT :R:' where 'VALUE "R'" is "ROCKET"). A consistent, flexible scheme

(assuming names and procedures share the same dictionary as suggested above)

would allow only 'EDIT "ROCKET'" and 'EDIT R'. 'EDIT ROCKET' could also

be allowed if the user could make his own procedure definitions that quote or

evaluate inputs at will--all in the interest of consistency, which is very

important to naive programmers. A further simplification would result if one

operation (e.g., 'DEFINE' or 'HOWTO') performed the functions of both 'EDIT'

and 'TO', since the only difference is the pre-existence of, or lack of, a

definition.

Noise words (e.g., 'OF' and 'AND' as in 'SUM OF 3 AND 5') should be

eliminated unless they are under user control. 'AND', for instance, has a very

strong meaning, almost equivalent to 'WORD', in many students' minds:

P SUM OF 3 AND 4 AND 5 AND 6

Logo should emulate Lisp in returning values for all commands and perhaps

printing these values at the top level rather than giving the message "THERE

IS NO COMMAND FOR..." when a student forgets to precede a function call

with a receiver for its reply. A user-controlled toggle for automatic value

printing would be a useful debugging aid. This would make 'STOP' and 'DONE'

equivalent to 'RETURN ''''', perhaps leading to their welcomed demise since

'EXIT' really does what their names suggest they do. Error messages should be

informative (e.g., "X IS ALREADY A LOGO OPERATION" not "X CAN'T BE A

PROCEDURE NAME"). Misleading error messages such as "OUTPUT CAN'T BE

USED AS AN INPUT IT DOES NOT OUTPUT" or "OUTPUT CAN ONLY BE

USED IN A PROCEDURE" should be avoided (the former is gibberish, the

latter should say something like "OUTPUT MUST BE PRECEDED BY A LINE

NUMBER"). Error messages should not end with a "?" unless the interpreter is

prepared to engage the student in a helpful dialog.

Editing and Filing. At one time or another, most students forget to enter

editing mode with 'EDIT' or 'TO' when trying to change a line in a procedure-

commands such as 20 and 'EDL 20' typed at Logo's top level resulted in the

messages "LINE 20 OF WHAT PROCEDURE?" and "EDIT WHAT? YOU ARE

NOT DEFINING ANYTHING" which may have misled students into trying the

following commands:

EDIT LINE 10 OF UNDOUBLE

ERASE LINE 6 IN RECTANGLE

IN TRI2

TO @35 OF RECTANGLE

Students often included extra words (some of which Logo had used in its

own messages) with operations such as 'EDIT' and 'LIST', which do not obey the

general· Logo evaluation scheme;

EDIT TO EVENPyou can't edit that.

ERASE :XI:erase what?

ENDagain definedUNDEFINE AGAINundefine needs a meaning.

LC OF FILE OF MARTAof can't be a file name

hence, error messages were often puzzling.

EDIT :XI:you can't edit that

ERASE TO SQUAREerase what?

LIST ALL FILESlist all what?

LIST NAMESsomething missing for list.

LIST ALL THAT WAS DONE TODAYlist all what?

GET FILE PC136 VOWELPfile can't be a file name.

As a convenience, it might be helpful to allow some default applications of

operations like 'LIST'. For instance, when 'LIST', 'EDIT', 'ERASE' or 'EDIT

LINE xx' is typed with no input, the default input would be the name of the

last procedure defined or executed. Similarly, a one-entry file could be gotten

without naming the entry.

The distinction between what is in Logo's immediate memory (workspace)

and what is on secondary storage (file entries) seems to be confusing even to

adults. By saving an entire workspace on an "entry", it is fairly easy to 'GET'

everything back at a later time. But since the workspace could contain the

appended results of several 'GET's from other entries (from other people's files

too), there is often unnecessary duplication in 'SAVE's. One should have the

ability to save partial workspaces (groups of procedures) on entries:

SAVE LIZ D AND UD AND SQUARE (Liz wanted to save individualprocedures on separate entries)

Student typing, some almost verbatim from the curriculum, occurred that

one might expect a reasonable computer-based tutor to handle. Merely

automating a programming curriculum by typing te)<t at the student

accomplishes little in dealing with such questions. Ideally a language

interpreter should "know" about concepts and problems the curriculum is

presenting and the intents of procedures the student is writing:

HOW MANY INPUTS DOES "MAKE" HAVE?

IS REQUEST A LITERAL?literal needs a meaning.NO IT DOESN'T

HOW MANY INPUTS DOES PRINT HAVE

IS "GEORGE" A WORD?

The ability to answer these questions is easily given to Logo because the subject

terminology (perhaps excepting "literal") is Logo's.

Debugging. Since Logo checks procedure lines for matching quotes and

colons at the time they are typed, it would also seem advantageous to report

other kinds of syntax errors at "define-time" rather than at "run-time". For

example, erroneous numbers of inputs for primitive commands or procedures,

and undeclared procedures or names (not defined globally or in the procedure's

title) could be reported before exiting editing mode, or upon request. The

student could act on these suggestions, editing further, or execute the partially

defined procedure while still in editing mode, or exit to work on something

else. This could at least help reduce the amount of time students spend in

discovering and correcting syntax errors one at a time. The idea of 'TRACE'

should be expanded to allow display of command-line execution, since the

pursuing of typically complicated commands rivals the complexity of recursive

procedure calls. An ability to undo the last command would also be very

helpful, as it is to LISP users.

Implications for Curriculum Design

In the first experiment, reports of tutors about student involvement in

different parts of the curricula and their own projects, real or planned, led to

changes in the presentation order of the concepts and in the techniques for

explaining certain concepts.

For Simper, most changes made for the second experiment centered upon

better motivations for: context, sequential execution, addressing and assembly

language. The machine's language of numerals would be taught before assembler

syntax so that students would grasp the latter's reason for existence as well as

its structure. The fact that different languages are appropriate for different

interactions with Simper was exploited in discussing computational context. The

intercommunication of instructions (e.g., via the registers) within programs was

also treated in terms of context. For Logo, the first experiment demonstrated

that procedures should be introduced early so students can create useful or

enjoyable tools right away.

So, for the second experiment, names were introduced first when naming

procedures and again when naming their inputs.. This definitely improved

student interest. Decision making was also introduced earlier in the second

experiment, in both curricula. Students could embark earlier on their own

projects, like games, some of which were used in parallel in Simper and Logo.

Early work with decision making helped the students in the second experiment

do better when the time came to combine it with other concepts needed, for

instance, in general recursion with stop rules.

In both experiments, the curriculum format (see Appendix 3) of path

pointers, questions, problems and things to try was generally well-received by

students. Certain connecting ideas or processes, such as how expressions are

evaluated and how program execution proceeds, are difficult to sequence on

paper. The flowchart-like diagrams with boxes and arrows (e.g., Appendix 3,

page 38L) were not particularly effective. The younger children had special

difficulty with these artifices, for the same reasons they had trouble with the

candy-machine problem on the preliminary test. Good yet static representations

of essentially dynamic processes are hard to come by. For Logo, the "brothers"

with knowledge clouds did test understanding when some of their states were

left blank, but were of little help in mapping this understanding into a

procedure. Good illustrations of effective metaphors are very important.

One of the questions addressed by this work has been "what are effective

metaphors for teaching the concepts (Table I) to naive programmers." For many

students, the concept of a context or computational environment proved most

difficult. In simplest form this reared itself in their confusing editing and

execution times/languages when interacting with the Logo or Simper

interpreters. Fresh students often gave editing commands to their running

programs, not realizing that their programs had, in effect, taken over the

machine and defined new languages. A linguist would probably say this is a

common problem in human languages as well. The most successful metaphor

used in this work involves thinking about the ability of an active entity

(machine/animal) to give its attention to some source (internal/external) of

messages and process these messages according to some rules (language).

Everyone knows what "giving attention" means to himself or herself. Linking

this to generalizations about machines (candy/computing) is all that's needed.

This applies directly to explaining functions too, if they are thought of as

translators.

In Logo, dealing with recursive procedures that return values was difficult

for almost all students. The above metaphor coupled with an analogy drawn to

a chain telephone call seemed most helpful. The complication is that each

caller must wait (on "hold" or to be called back) until the "callee" has an

answer to give. The success fo this tutoring device raised hopefully clearer

alternatives to 'RETURN' such as 'REPLY' in Logo. The way in which Logo

uses its internal pushdown stack for saving local contexts during recursion (or

the equivalent Simper programming) links straightforwardly with the attention

metaphor above.

Play-acting out programs, particulary Logo, was tried in both experiments

(e.g., Appendix 3, page 39L) with mixed results. It seemed most effective when

used to explore command evaluation, coupled with the telephone metaphor and a

wary likening of inputs to be instantiated to mailboxes in need of letters. For

simple syntactic problems (e.g., how many 'WORD's to use) a little applied logic

often produced helpful analogies (e.g., for n values use n-1 'WORD's because it

takes n-1 dabs of glue to stick together n blocks).

Case Studies

The problem encountered by two second-experiment students at each point

in each curriculum will be discussed in order to expose both their differences

and commonalities in thought when faced with the task of learning their first

programming languages. They will be referred to by their rank position on the

pretest (Figure lOb) and discussed separately for two languages.

Simper. Student 6 worked relatively seriously and, from the start,

carefully and thoroughly followed the curriculum instructions and examples.

She was not uncomfortable with the primitive nature of the Simper machine

language nor with the basic commands involved in editing. Addressing and

successor executions seemed common-sensical to her. After some brief problems

with programs that ran off their ends or jumped to nonexistant instructions,

she had no further trouble with program control. Her first major project was

the number-guessing game from the curriculum. She often did much of the

work at home, bringing it the next day to tryout. She made two important

errors. First, picking the number to be guessed but failing to store it in

memory for later comparison with the user's guess. Second, using the wrong

register in her decision-making instruction. Both errors can be thought of in

terms of misappropriating the internal context of the machine at runtime. She

also needed help in deciding that the program should pick the number before

the user guesses. This would not matter if only one guess were to be allowed.

Once. her program was working, she used it a great deal and modified both the

size of the numbers selected and the hints given when a guess was wrong.

Student 6 went On to other work, but had saved her guessing-game and

often recalled it to use. She worked on indirect addressing with no problems.

The next important project involved the concept of a data-structure consisting

of 5 characters stored in one memory cell. Again she had little difficult and

spent time at home working on her program. When the curriculum called for a

stop rule to be added to the program for printing 5 characters from a cell, she

picked the correct rule wi th no help. She still had some trouble matching

registers correctly in what amounted to a several-instruction program. She also

generated a control error by jumping too far back in her program on each loop

circuit and re-initializing a memory cell used for counting. This class of error

persisted in her work for a few days. A further error in clearing memory at

the wrong time prevented her stopping rule from functioning and her program

ran on and on. After correcting these errors, it was obvious that her program

I

II

I

Page 106

almost worked but stored only a partial result in memory--the full result being

in a register. She noticed this with no help and corrected the problem. A

subsequent attempt at a similar program demonstrated that complex control was

still not mastered--a jump was redundantly included and a target symbol was

placed one instruction late in the program. In addition, context problems with

assumed register content recurred. The program was eventually corrected with

help. She then went on to use the graphics system and constructed several

iterative drawing programs without error. She then began the Logo curriculum.

Student 14 began Simper and had difficulty immediately in understanding

successor execution. His reaction to an erroneous program was to erase it

rather than edit it. He was mystified by the first program in the curriculum

because, when run, it gave no visible result until memory was displayed after

execution. This resulted from a misreading of the curriculum instructions. As

a result, he required more than average amounts of tutoring. He had great

difficulty understanding the need to match register names when communicating

values among instructions. When introduced to addressing, he attempted to

address a value by content. That is, he used an address equal to the value, not

an arbitrary address, as desired. In doing so, his first such program generated

overflows by dividing by empty cells (0 values). He was helped to correct these

problems and still preferred to erase entire programs rather than edit. In

working on one program from the curriculum, he demonstrated a typical context

error: typing editing commands to a running program. At this time he decided

to review the entire curriculum. He repeated some previo.us errors, in.

particular, use of the wrong registers for inter-instruction communication.

Since he was in Group III, he was also learning Logo and some Logo editing

commands crept into his Simper interactions. His review of addressing helped

him clear up his old confusion about content versus location. In reconstructing

one curriculum program, he produced a control structure that jumped to a

wrong location. He also neglected a printing instruction even though he created

a value in a register to be printed. Context errors from typing editing

commands to running programs persisted.

He made several syntax errors that indicate he doesn't really understand the

3-field structure of Simper instructions. Most notable was an attempt to use

multiple address fields to store multiple characters in a register. Again a

control problem appeared as he started the guessing-game project. His program

had a jump to a redundant instruction. His corrected program worked but

printed out a message backwards. When translating a 'JUMP' to a 'COMPARE'

he left in an unnecessary instruction prior to the jump that prevented the

program from operating. He repeated this error twice. Upon first exposure to

symbols, he forgot to attach them to memory cells and so generated illegal

addresses upon running the programs. In a later program to realize the

function 2x+9, he used an address literally and so wrongly operated on an

instruction in the program body. The data-structure program he produced

contained several bugs including a misaimed jump and a redundant instruction

that is never executed. With help he tried several times, but never quite

understood how the program was to function. Iteration and symbolic addressing

remained unmastered.

Logo. Student 6 had begun Logo after leaving Simper. She grasped

intraprocedure control quickly but failed initially at using nested

(sub)proceudres. Once helped she went on to create her own version of a

simple recursive procedure to print her name. She was initially confused about

procedures that return values and what to do with the value. She had no

trouble with simple command syntax, but did have trouble with the colon

notation denoting named values--she either neglected the colons in the command

line or put them around constants. After a few such errors she seemed to

understand name/value associations in Logo. A series of several procedures are

faced in the curriculum which demand successively more complex command lines.

She used 'LAST' to mean "place this character last" not "take the last

character". Commands that build strings out of parts tended to get too few

'WORD's. She used the same name for both inputs of a 2-input procedure thus

getting only the final instantiation when it is called. She considered 'FIRST' to

act destructively on its input. She failed to use a building block sub-procedure

at an opportune time. After several string manipulating procedures she

mastered the command syntax, but did not quite know when to use 'RETURN'

appropriately. She failed to use a recursive call when it was of obvious

necessity. She used 'RETURN's successively, as if they append to an output

message rather than terminate execution.. She worked on the first major

project--the guessing-game and needed help understanding 'BOTH'. In more

complicated projects like 'REVERSE' she demonstrated understanding of inputs

and control but not quite of recursive 'RETURN's which she tended to leave

dangling so that values were fed to Logo not the calling procedure. The use of

stop rules was no problem for her.

Student 14 had been learning Simper at the same time as Logo. He began

by typing literally from the curriculum (e.g., "CONTROL-NU). He retyped

procedures rather than use edit. He attempted to elicit information from Logo

by having it print sentences which, of course, have no meaning to Logo. He

tended to use previous procedures' structures as solutions to new problems. He

had trouble matching input names to procedure command lines. Prefix notation

seemed no problem to him, but he did have trouble providing enough inputs to

operations in command lines. He also forgot basic syntax items like line

numbers and colons. The major project of the guessing game failed on first try

because it tested a cOnstant rather than a computed value. At this point he

helped another sutdent with earlier work. After much help he had a working

guessing game which he used alot. Some Simper commands appear. In the

more complicated recursive procedures he neglected not only recursive returns

but stop rules. He tended to misplace stop rules sO they never got executed.

Once they were working he enjoyed observing such procedures operate on long

inputs under 'TRACE'. When the opportunity arose to use an already existing

procedure as a tool in solving another problem, he rarely capitalized on it. He

began using the graphics system and experimented with various kinds of

pictures drawn from building block procedures he'd been given, but produced

little original work.

Summary

The two students, whose work has been outlined, suggest the range of

abilities that were present during both experiments. Some students took to the

curricula and languages quickly and easily, while others did not. As has been

discussed, and as Figures 17 and 18 also suggest, the preliminary test seems to

order students approximately on ability to complete the curricula. It also

seems, from subjective evaluations of the students, to order them approximately

on mastery. The more important question of how students learn the concepts i&..·

only answerable from case-study data.

The .metaphors outlined earlier seem to work because they help students

identify with the process they are trying to understand. The two most common,

virtually universal misunderstandings of all the students were: (1)

misunderstandings of linguistic/computational context, and (2) ill-defined

intents. The former applying to both the storage/passing of information within

their programs and their interactions with the interpreters. The latter, or

fuzzy program specifications, amounts to wishful thinking, wherein the

particular interpreter was expected to read the student's mind and run correctly

even though, for instance, a command had been left out. Leaving out recursive

'RETURN's, as mentioned earlier, is a typical example in which the student

expects the computer to be the command whose value is not returned. A brief

categorization of all errors appears in Table XI.

In terms of the concepts originally selected as important to learning

programming (Table I), a somewhat different ordering on difficulty for each

student is implied by individual case-studies, at least in the second experiment

whose data are best. Typically, however, individual orderings approximate the

sequence listed in Table I, with the notable exceptions of: concept 1, due to

user/machine context errors, falls at about position 5; concepts 14, 15, and 17,

because of internal program-management errors and common difficulty in

starting on a reasonable program design, fall last; and concepts 5 and 9 lump

together at position 9.

Wi th regard to programming languages and their influence on students, the

data strongly suggest that languages should be syntactically consistent, and

powerful in both editing and execution capabilities. As one student said after

her first hour with Logo: "If computers can understand languages like Logo,

can't they understand English?"

Table XI

Categoriz~tion of Observed Student Errors and Misconceptions

Use of Language Syntax

Predicates difficult to master, especially combinations such as'BOTH'I'EITHER'.

Making up nonexistent noise words analogous to Logo's.Misunderstanding deferred-command parsing in Logo--inputs are read

backwards.Using infix and postfix rather than the Logo prefix.Trying to use ditto marks to copy parts of a line to next line.Existence of "holes" in Simper programs.Literal interpretation of Simper address field.Thinking that changing (Simper) target cell's content changes all

instruction's address fields that reference that cell.Forgetting to put a value in a (Simper) target cell before accessing

it.Testing the wrong register in Simper loops.

Sequencing

Not knowing any or the simplest stop condition on an iteration orrecursion.

Confusion between iterative and recursive techniques--input andreturn values.

Jumping inappropriately..Multiple commands per line.Improperly communicating Simper instructions that destroy rather

than pass on contents of registers.

Use of Procedures

Meaning of input values (using colon: in Logo for both constantsand variables).

Thinking procedure names must say what they. do in order to work.Distributed or forgotten inputs. .-Returns from looping procedures unforeseen.Names of inputs not distinct or assumed to computationally relate to

a value (e.g., see page 93).Names of inputs not the same in title and use.

Returning Values

Simple recursion and 'EXIT' is easy, but returning value to self isnot.

Procedure becomes, semantically, the value or function to bereturned.

Last procedure called, in series of calls, returns value for the entireseries.

Distinction between Logo 'DONE' and 'RETURN'.

Table XI (continued)

Storage/~emory

Not understanding that a 'SAVE' can destroy a previously filedprogram.

Understanding memory in Simper as read-copy/write-destroy; andthat it is permanent until changed by a program.

Editing Versus Runtime

Problems editing Logo titles.Hard to think about runtime when editing (thinking that editing

actually executes).Understanding what 'RUN' means for a program--that the machine's

linguistic appearance to the user is redefined by the program.

Problem Solving ~ethods

Surprised that a problem can be solved or that the computer cancarry out a certain command.

Failure to generalize previous solutions to present problem.Inability to break problem solution into program steps to write.~ultiple-line solutions rather than well-structured iteration or

function calls.Failure to see minimal solutions.Failure to exploit the style of the programming language (such as the

possibility for extra inputs to act as counter or method ofpassing conditional information).

References

Bassala, G. Man and machine (book review). Science, 187, 248-250, 24 January,1975.

Berry, P. Pretending to have (or to be) a computer as a strategy in teaching.Harvard Educational Review, 34, 383-401, 1964.

Bitterman, M. The comparative analysis of learning. Science,. 188, 699-709, 16May, 1975.

Bloom, B. Thought-processes in lectures and discussions. The Journal ofGeneral Education, 1953, 7, 160-169, April, 1953.

Bloom, B., & Broder, L. Problem-solving processes of college students. Chicago:The University of Chicago Press, 1950.

Bradley, J. Distribution-free statistical tests. Englewood Cliffs, N.J.: PrenticeHall, 1968.

Brainerd, C. The origins of number concepts. Scientific American, March, 1973.

Brand, S. Two cybernetic frontiers. New York/Berkeley, Calif.: RandomHouse/The Bookworks, 1974.

Bredt, T. A computer model of information processing in children. TechnicalReport No. CSlOO. Stanford, Calif: Computer Science Department,Stanford University, 1968.

Brown, J., & Burton, R. SOPHIE--A pragmatic use of AI in CAL TheProceedings of the ACM National Conference, San Diego, 1974.

Brown, J., & Rubinstein, R. Recursive functional programming for students in thehumanities and social sciences. Report No. 27. Irvine, Calif.:Department of Information and Computer Science, U. C. Irvine, 1973.

Buxton, J. (Ed.) Simulation programming languages. Amsterdam: NorthHolland, 1967.

Campbell, D., & Erlebacher, A. How regression artifacts in quasi-experimentalevaluations can make compensatory education look harmful. In J.Helmuth (Ed.), Disadvantaged child. Vol. 3, Compensatory education:

. A national debate. New York: Bruner-Mazel, 1970.

Cannara, A. Toward a human computer language. Creative Computing,September-October, 1975.

Cannara, A., & Weyer, S. A study of children's programming. Proceedings ofthe 1974 Conference on Computer-Based Learning Systems, University ofHamburg, Federal Republic of Germany, August, 1974.

Cannara, A., & Weyer, S. Programming languages for children. The SecondAnnual Computer Science Conference, Detroit, February, 1974.

Carbonell, J. Mixed initiative man-computer instruction. Report No. 1971).Boston: Bolt, Beranek & Newman, 1970.

Chai tin, G. Randomness and mathematical proof. Scientific American, May,1975.

Chapanis, A. Interactive human communication. Scientific American, March,1975.

Dahl, 0., Dijkstra, E., & Hoare, C. Structured Programming. .NewYork:Academic Press, 1972.

Davis, M. (Ed.) The undecidable. Hewlett, New York: Raven Press, 1965.

Davis, M., & Hersh, R. Nonstandard analysis. Scientific American, June, 1972.

Drake, S. The role of music in Galileo's experiments. Scientific American, June,1975.

Dwyer, T. A. An experiment in the regional use of computers by secondary schools.Final Report, NSF-OCA-GJ1077-S0LO, 1972.

Ellis, A. The use and misuse of computers in education. New York: McGrawHill, 1972.

Evey, R J. The theory and applications of pushdown store machines. Unpublisheddoctoral dissertation, Harvard University, 1963.

Feigenbaum, E., & Feldman, J. (Eds.) Computers and thought. New York:McgrawcHill, 1963.

Feldman, J. A formal semantics for computer languages and its application in acompiler-compiler. Communications of the ACM, January, 1966.

Felix, L. The modern aspect of mathematics. New York: Basic Books Inc., 1960.

Fenichel, R, & Weizenbaum, J. Computers and computation. San Francisco: W.H. Freeman and Co., 1971.

Fenichel, R, Weizenbaum, J., & Yochelson, J. A program to teachprogramming. Communications of the ACM, March, 1970.

Feurzeig, W., Papert, S., Bloom, M., Grant, R, & Solomon, C. Programminglanguages as a conceptual framework for teaching mathematics. ReportNo. 1889. Boston: Bolt, Beranek & Newman, 1969.

Feurzeig, W., & Lukas, G. A programmable robot for teaching. TheInternational Congress of Cybernetics and Systems, Oxford, England,1972.

Feurzeig, W., & Lukas, G. Logo: A programming language for teachingmathematics. Educational Technology, March, 1972.

Feurzeig, W., Lukas, G., Faflick, P., Grant, R, Lukas, J., Morgan, C., Weiner,W., & Wexelblat, P. Programming languages as a conceptual frameworkfor teaching mathematics. Report No. 2165. Final Report, NSF-C-615,Vols. 1-3. Boston: Bolt, Beranek & Newman, 1971.

Fischer, G. Material and ideas to teach an introductory programming course usingLogo. Irvine, Calif.: Department of Information and ComputerScience, U. C. Irvine, 1973.

Fletcher, J. Computer science seminars on pedagogical techniques and methodsfor evaluation. Seventh Annual Systems Symposium, Princeton, March1973.

Folk, M., Statz, J., & Seidman, R. Syracuse university Logo project. Report No.3. Final Report, NSF-TIE-GJ32222-3. Syracuse, New York: SyracuseUniversity, 1974.

Forsythe,A., Keenan, T., Organick, E., & Stenberg, W. Computer science: Afirst course. New York: Wiley, 1969.

Fromkin, V. Slips of the tongue. Scientific American, December, 1973.

Gardner, R., & Gardner, B. Early signs of language in child and chimpanzee.Science, 187, 752-753, 28 February, 1975.

Ginsberg, S. The mathematical theory of context-free languages. New York:McGraw-Hill, 1966.

Givens, W. Implications of the digital computer for education in themathematical sciences. Communications of the ACM, September, 1966.

Goldberg, A. Computer-assisted instruction: The application of theorem proving toadaptive response analysis. Technical Report No. 203. Stanford, Calif.:Institute for Mathematical Studies in the Social Sciences, StanfordUniversity, 1973.

Goldberg, A., Levine, D., & Weyer, S. Three sample instructional programsfrom Stanford University. Computers in the instructional process:Report of an international school. Ann Arbor, Mich.: ExtendPublications, 1974.

Goldstein, 1. Understanding simple picture programs. Technical Report No. 294.Cambridge, Mass.: Artificial Intelligence Laboratory, MassachusettsInstitute of Technology, 1974.

Gries, D. Compiler construction for digital computers. New York: Wiley, 1971.

Harlan, J. Our vanishing genetic resources. Science, 188, 618-621, 9 May, 1975.

Hoare, C. Proof of a program Find. Communications of the ACM, January,1971.

Holton, G. On the role of themata in scientific thought. Science, 188, 328-334,25 April, 1975.

Jackson, P. Life in classrooms. New York: Holt, Rinehart and Winston Inc.,1968.

Jaynes, E. Confidence intervals versus Bayesian intervals. The InternationalSymposium on Foundations of Probability and Statistics and StatisticalTheories of Science, University of Western Ontario, May, 1973.

Kay, A. Personal dynamic media. Xerox Learning Research Group, Xerox PaloAlto Research Center, Palo Alto, CA., June, 1975.

Kay, A. A personal computer for children of all ages. Proceedings of the ACMNational Conference, Boston, 1972.

Kay, A. A dynamic medium for creative thought. Meeting of The NationalCouncil of Teachers of English, Minneapolis, 1972.

Kimball, R. Self-optimizing computer-assisted tutoring: Theory and practice.Technical Report No. 206. Stanford, Calif.: Institute for MathematicalStudies in the Social Sciences, Stanford University, 1973.

Knuth, D. MIX. Reading, Mass.: Addison-Wesley Series in Computer Scienceand Information Processing, 1970.

Knuth, D. Fundamental Algorithms. Reading, Mass.: Addison-Wesley, 1968.

Koestler, A. The roots of coincidence. New York: Vintage Books/RandomHouse, 1973.

Kolata, G. Communicating mathematics: Is it possible? Science, 187, 732, 28February, 1975.

Kolers, P. Experiments in reading. Scientific American, July 1972.

Kruskal, W. Letter to the editor, Science, 188, 10, 4 April, 1975.

Kruskal, J. Multidimensional scaling by optimizing goodness of fit to anonmetric hypothesis. Psychometrika, 29, 1-27, 1964.

Ledgard, H. Ten mini-languages: A study of topical issues in programminglanguages. Computing Surveys, 3, 115-146, September, 1971.

Levison, M., Ward, G., & Webb, J.simulation. Minneapolis:

The settlement of Polynesia. A computerUniversity of Minnesota Press, 1973.

Lorton, P., & Muscat, E. Computer utilization at the secondary school level: Amodel for computer assisted career education. In G. Goos & J.Hartmanis (Eds.), Lecture notes in computer science. 17, Berlin:Springer-Verlag, 1975.

Lorton, P .. & Slimick, J. Computer-based instruction in computer programming.Fall Joint Computer Conference, Las Vegas, 1969.

Manis, V. A machine independent implementation of Logo. Unpublished doctoraldissertation, University of British Columbia, 1973.

Manna, Z. Introduction to the mathematical theory of computation. New York:McGraw-Hill, 1972.

Mauchly, J. Mauchly on the trials of the Eniac. IEEE Spectrum, April, 1975.

Maurer, W. Programming. San Francisco: Holden-Day, 1968.

McLaughlin, M. Evaluation and Reform: The elementary and secondary educationact of 1965, Title I. Report No. R-1292-RC. Santa Monica, Calif.:The Rand Corporation, 1974.

Merton, R. Thematic analysis in science: Notes on Holton's concept. Science,188, 335-337, 25 April, 1975.

Milner, S. The effects of computer programming on performance inmathematics. Annual Meeting of the AERA, New Orleans, February,1973.

Minsky, M. (Ed.) Semantic information-processing. Cambridge, Mass.: MITPress, 1968.

Minsky, M. Computation: Finite and infinite machines. Englewood Cliffs, N.J.:Prentice-Hall, 1967.

Morris Jr., J. Another recursion induction principle. Communications of theACM, May, 1971.

Nedelsky, L. Evaluation of essays by objective tests. The Journal of GeneralEducation, 7, 209-220, April, 1953.

Newell, A., & Simon, H. Human problem solving. Englewood Cliffs, N. J.:Prentice-Hall, 1972.

Nievergelt, J. The automation of introductory computer science courses. TheInternational Computing Symposium, Davos, Switzerland, September,1973.

Nilson, N. Problem solving methods in artificial intelligence. New York:McGraw-Hill, 1971.

Oettinger, A., & Marks, S. Run, computer run: The mythology of educationalinnovation. Boston: Harvard Press, 1969.

Papert, S. Teaching children thinking. IFIP Conference on Computer Education,Amsterdam, August, 1970.

Piaget, J. Genetic epistemology. New York: Columbia University Press, 1970.

Pirsig, R. Zen and the art of motorcycle maintenance. New York: Morrow & Co.,1974.

Polya, G. How to solve it. Princeton, N.J.: Princeton University Press, 1957.

Puri, M. (Ed.) Nonparametric techniques in statistical inference. London:Cambridge University Press, 1970.

Reisfeld, R., & Kahan, B. Markers of biological individuality. ScientificAmerican, June, 1972.

Reynolds, J. Gedanken: A simple typeless language based on the. principle ofcompleteness and the reference concept. Communications of the ACM,May, 1970.

Roman, R. Logo: A student manual. Pittsburgh: Learning Research andDevelopment Center, University of Pittsburgh, 1972.

Rozeboom, W. The fallacy of the null hypothesis significance test. In D.Morrison & R. Henkel (Eds.), The significance test controversy.Chicago: Aldine Publishing Co., 1970.

Rubinstein, R. Computers and a liberal education: Using Logo at theundergraduate level. Irvine, Calif.: Department of Information andComputer Science, U. C. Irvine, 1974.

Salomaa, A. Theory of automata. London: Pergamon Press, 1969.

Scribner, S., & Cole, M. Cognitive consequences of formal and informaleducation. Science, 182, 553-559, 9 November, 1973.

Serin, J. Letter to the editor. Science, 189, 86-88, 11 July, 1975.

Smallwood, R. A decision structure for teaching machines. Boston: MIT Press,1962.

Steel, T. (Ed.) Formal-language description-languages. Amsterdam: NorthHolland, 1966.

Steen, L. Foundations of mathematics: Unsolvable problems. Science, 189, 209210, 18 July, 1975.

Stent, G. Limits to the scientific understanding of man. Science, 187, 10521057, 21 March, 1975.

Stent, G. Letter to the editor, Science, 189, 504, 15 August, 1975.

Swinehart, D., & Sproull, R. SAIL. Sailon No. 57.2, Stanford, Calif.: StanfordArtificial Intelligence Laboratory, 1971.

Toomre, A., & Toomre, J. Violent tides between galaxies. Scientific American,December, 1973.

Tukey, J., & Wilk, M. Data analysis and statistics: Techniques andApproaches. The Symposium on Information Processing in Sight SensorySystems. California Institute of Technology, November, 1965.

Vacroux, A. Microcomputers. Scientific American, May, 1975.

Weyer, S., & Cannara, A. Children learning computer programming: Experimentswith languages, curricula and programmable devices. Technical ReportNo. 250. Stanford, Calif.: Institute for Mathematical Studies in theSocial Sciences, Stanford University, 1975.

Weyer, S., & Cannara, A. Programming projects for children: Graphics andspeech synthesis. The Second Annual Computer Science Conference,Detroit, February, 1974.

Winograd, T. When will computers understand people? Psychology Today, "May,1974.

Winograd, T. Procedures as a representation of data in a computer program forunderstanding natural language. Project MAC TR-84. Cambridge,Mass.: Massachusetts Institute of Technology, 1971.

Wirth, N. Euler: A generalization of Algol, and its formal definition.Communications of the ACM, February, 1966.

Wittrock, M. (Ed.) Changing education: Alternatives from educational research.Englewood Cliffs, N.J.: Prentice-Hall, 1973.

Worthen, B., & Sanders, J. Educational evaluation: Theory and practice.Worthington, Ohio: Charles Jones Publishing Co., 1973.

Appendix 1 Spm

This appendix documents the syntax and semantics of a language (Spm)

designed by the author but never used in any experiments. It simulates a

string-processing machine in which one operation, assignment CISNOW'), plays

the central role. First, a comparison of Logo/Spm phrasing:

Literal "DONALD" [DONALD]

Name/value linking MAKE "DONALD" "DUCK" @[DONALD] ISNOW [DUCK]or DONALD ISNOW [DUCK]

Name evaluation THING OF "DONALD"or just :DONALD:

@[DONALD] or DONALD

Indirect naming

String appending

MAKE :DONALD: "FOWL" @@[DONALD] ISNOW [FOWL]or @DONALD ISNOW [FOWL]

WORD OF "ABC" AND "D" STACK ISNOW [ABC];STACK ISNOW [D];NEXT ISNOW APPEND;

String definitions(substitutions)

. Input/output

Labelling

Storage release

Operation definition(dialogs)

Execution call

Recursion

ABBREVIATE "WORD"AS "JOIN"

PRINT JOIN "ABC" "D"

line numbers as below

automatic

~TO DD oW: :C:@lO PRINT JOIN oW: :C:@END

+-DD "ABC" "D"ABCD

~TO RECURSE@1Q P "RECURSE"@20 RECURSE@END .~RECURSE

RECURSE

[PUSH] ISFOR [STACK ISNOW];[DO] ISFOR [NEXT ISNOW];[TYPE] ISFOR [TTY ISNOW];

PUSH [ABC]; PUSH [D];DO APPEND; TYPE STACK;

LAB ISNOW NEXT; DO LAB;

FORGET LAB;

DD ISNOW [DO APPEND;TYPE STACK;@[] ISNOW NEXT];

PUSH [ABC]; PUSH [D];DO DD;ABCD

RECURSE ISNOW [TYPE [RECURSE];DO RECURSE;];DO RECURSE;RECURSE...

asll and "or". '. The paired meta-symbols

andSpm Syntax. The meta-symbols ..< >

I

( )

Page 120

mean, respectively, "rewrite

and {} mean, respectively,

"a non-terminal", "one of" and "optional ll• Spaces may be ignored. Note that

( ) < > and .. appear both as terminal and meta-symbols:

<program> .. {<blank>} {<statement> {<blank>}} ; {<program>}

<blank> .. <non-printing teletype motion character> {<blank>}

<statement> .. <comment> I <assignment> I <substitution) 1 <forget><test> {<blank>} ,:. {<blank>} <statement>

<comment> .. <literal> {{<blank>} <comment>}

(assignment) .. <destination> ISNOW (<source> I {<blank>} <literal»

(substitution) .. «destination> I <literal> «blank>}) ISFOR«source> I {<blank>} <literal»

<forget> .. FORGET <source>

<test> .. (IFEMPTY I IFNOTEMPTY) «source> 1 <literal»

<literal> .. [ <balanced string> ]

<balanced string>.. {<string>} {<balanced string>} {<literal>} {<string>}

<destination>

<source>

.. «name> 1 <indirect name» <blank> I<literal name> {<blank>}

.. <blank> <name> I{<blank>} «literal name> 1 <indirect name»

<literal name> .. @ {<blank>} «literal> I <literal name»

<indirect name> .. @ {<blank>} «name> I <indirect name»

<string> .. <blank> 1 «name> 1 : 1 ; I @ ) {<string>}

<name> .. (A 1 B 1 c 1 DIE 1 FIG I H 1 I 1 J 1 K 1 LIM 1NIOIPIQIRISITIUIVIWIXIYIZI0111 2 13141516171819111"1#1$I%I&I'ICI)I*I+I,I-I.I/I<I= 1 > 1 ? 1 1 I") {<name>}

Semantics. The Spm machine consists of (a) a processor, which interprets

strings in the Spm language defined above; (b) an arbitrary number of memory

cells, each capable of storing a balanced string of arbitrary length; and (c) two

pushdown stores called 'STACK' and 'NEXT', each consisting of an ordered set

of memory cells of which only that cell bearing the name of the set is

immediately accessible. New memory cells are created as needed to satisfy

assignments. Any existing accessible cells, except 'STACK' and 'NEXT', can be

released. The Spm machine also maintains an inaccessible and variable stock of

cells for satisfying 'ISFOR' statements and 'STACK' and 'NEXT' manipulations.

Certain strings have special meaning to the Spm machine as names,

primitive operations. Names which Spm automatically associates with specific

memory cells are: 'TTY', 'STACK' and 'NEXT'. Other names are defined by

the execution of assignments. All accessible cells must necessarily have distinct

names. Spm operations are predefined names which cause specific activities of

the machine when it encounters them during the execution of statements.

'ISNOW', 'ISFOR', 'FORGET', 'IFEMPTY', 'IFNOTEMPTY', '@', ';', ':', T' and ']'

have such effect. The two pushdown stores, whose accessible cells are named

'STACK' and 'NEXT', have special properties: (a) if either 'STACK' or 'NEXT'

appears as the destination in an assignment, the machine attaches a new cell to

the accessible end of the appropriate ordered set of cells. The new cell is loaded

with the value of the source and the name 'STACK', or 'NEXT' as appropriate,

is associated with this new cell rather than with the previously accessible cell;

(b) if either 'STACK' or 'NEXT' occurs as a source in an assignment, a

substitution or a (forget>, the Spm machine uses the accessible cells's content,

and releases the cell. The name 'STACK' or 'NEXT', as appropriate, is then

associated with the next cell in the corresponding ordered set of cells. The

same action results when either 'STACK' or 'NEXT' appears as a destination in

a substitution statement; (c) no change in the structure of 'STACK' or 'NEXT'

is made if either appears as a source in a test.

Spm Primitives

Symbols

NEXTSTACKTTY

Operations

ISNOWISFORFORGETIFEMPTYIFNOTEMPTYAPPENDHEADTAILAFTER@

.[]

'NEXT' always contains the string to be executed next by the Spm machine.

The machine obtains one statement after another from this string by scanning

the value of 'NEXT' from left to right until a ';', not part of a literal, is

encountered. The scanning process removes all characters up through the ';'

from 'NEXT', shortening its content as execution procedes. When the last

statement in 'NEXT' has been executed, the current cell is released and replaced

by that directly beneath it. Should 'NEXT' ever be exhausted of cells, the Spm

machine will automatically attempt to fill 'NEXT' with characters from the

teletypewri ter ('TTY'). If a statement cannot be executed, the machine prints a

message and again goes to the teletypewriter for input. Note that this is

analogous to execution of the statement 'NEXT ISNOW TTY'. 'STACK' is the

accessible cell in the general pushdown store and may have as value any string.

'TTY' is the user's terminal. Assignment to it causes the assigned value to be

printed. Assignment from it to a destination obtains characters from the

typist. Its value is not maintained by Spm, sO characters disappear on the way

in or out as typing proceeds at the terminal. Its value is '[]' when input or

output has been completed.

'ISNOW' is the means for changing the content of the Spm machine's

memory. When a name is used for the first time in an assignment, the

machine obtains a new cell in which to store the assigned value and associates

the name with this cell. 'lSFOR' is a simple symbol/string substitution

mechanism. After it is executed, the Spm machine will automatically substitute,

for any occurrences of the value on the left of the 'ISFOR' in the text of any

statement scanned from 'NEXT', the value on the right. This 'amounts to a

simple transformation of the Spm language to suit the user. Recursive

substitutions are not allowed. 'FORGET' is the means for releasing names and

their associated memory cells from the Spm machine's memory.

'IFNOTEMPTY' and 'IFEMPTY' are tests which, if the value tested is not

'[]' or is '[]', respectively, will execute the subsequent statement. Otherwise, the

statement is skipped.

'APPEND' joins a character to the end of a string. The character is

assu'med to be in the top cell of 'STACK', with the string immediately beneath.

It returns the resultant string as the value of 'STACK'. If a string is used for

the character, only its first character will be appended. 'HEAD' accepts a

string in 'STACK' and returns the first character of that string in 'STACK'.

'TAIL' is like 'HEAD', but returns all characters in the string after the first is

removed. For 'AFTER', 'STACK' and the cell beneath it each contain a

character. If the character in 'STACK' occurs before the other character in the

lexicographical ordering defined for the characters of the Spm alphabet, the top

character is removed from 'STACK'. Otherwise, both 'STACK' cells are removed

and the value of '[]' given to 'STACK'. If strings are supplied as values, only

the first character of each will enter into the comparison.

'@' indicates that the value of the string which follows should be

interpreted as a name. Note '@[ABC]' and 'ABC' are equivalent. ';' terminates

an Spm statement. ':' indicates the beginning of a statement in a test. T' and

'J' respectively denote the start and end of a literal. Note that '[' and. 'J' must

occur in pairs according to the syntax. There is no legal way to obtain either

bracket singly in a piece of executable text. They may be obtained from '[J'

however, with the 'HEAD' and 'TAIL' functions. Some details of Spm phrasing

follow:

String constant

Empty string

Assignment

Name evaluations

Recursive naming(unlimited indirect

addressing)

Using 'STACK'(produces):

Using tNEXT'(program control,

produces):

SubstitutionsISNOW];

Input!output(types out "ABCD")

Storage release

Operation defining

Execution(types out "ABCD")

Recursion

Stack release

Premature return

[DONALD] (literal)

[]

@[DONALD] ISNOW [DUCK] or DONALD ISNOW [DUCK]

@[DONALD] or just DONALD both have the value DUCK

@@[DONALD] ISNOW [FOWL] or @DONALD ISNOW [FOWL]

STACK ISNOW [ABC]; STACK ISNOW [D];+-----+I D 1<-- STACK+-----+1 ABC 1+-----+

NEXT ISNOW APPEND; TTY ISNOW STACK;

+----~-----------------+ +-------+1TTY ISNOW STACK 1<-- NEXT 1ABCD 1<-- STACK+----------------------+ +-------+

[PUSH] ISFOR [STACK ISNOW]; [DO] ISFOR [NEXT

[TYPE] ISFOR [TTY ISNOW];

PUSH[ABC]; PUSH[D]; DO APPEND; TYPE STACK;ABCD

FORGET DONALD;

DD ISNOW [DO APPEND; TYPE STACK;];

PUSH [ABC]; PUSH [D]; DO DD;ABCD

RECURSE ISNOW [TYPE [ABCD]; DO RECURSE;];DO RECURSE;ABCDABCDABCDABCD...

@[] ISNOW STACK;

@[] ISNOW NEXT;

-."

Appendix 2 Aptitude-Testing Details

An Example of Commercial Test Evaluation

The example derives from remarks in the published manual for one of the

programming tests examined. The validity of that test was assessed by three

studies: (1) correlation of test scores and grades of three groups of

programming trainees, (2) correlation of test scores and overall performance

ratings by supervisors of programmers, and (3) a study like that of (2) in

which grades on a training course were also available. Studies (1) and (3) both

assumed, without discussion, that the testing done during training was itself a

valid measure of programming ability. Studies (2) and (3) both assumed that

ratings by superiors were similarly valid. Study (1) indicated that, of fifteen

relevant correlations between subtest scores and trainee groups, eight were of

statistical (normal theory) significance. And only one subtest was significantly

correlated with trainee performance over all groups, in spite of the fact that

the overall test/training correlation for each group was significant.

Interestingly, the most variable subtests were those which relied heavily on time

and repetition. In Study (2), three of five subtest correlations and the overall

correlation were significant but small; and the two remaining subtests were

those which exhibited variable or minimal correlation with performance in

study (1). Unfortunately, the ratings used as the validating measure in (2) were

not confined to programming ability and included such things as attitudes.

Therefore, study (2) is invalid. Study (3) found three subtests significantly

correlated with training course grades, but one of the three had not been

significantly correlated with grades for any group in study (1). Furthermore,

the ra tings used in the other half of study (3) were virtually uncorrelated with

subtest results. The brochure went on to state that these ratings and job

tenure were correlated more strongly than anything else in both halves of the

study--the suggestion being that low correlations must be expected when

evaluations place high value on relatively invalid properties· (i.e., tenure). An

alternative observation can be made which applies to any correlational

procedure: the sample variance of a measured property may be so low that

apparent but spurious correlations with another measure arise. In study (3),

the test scores could have had low variability for good reason: the testees could

have been of very nearly the same competence. In any event, none of the

studies provided a clear validation of this particular test for programming

aptitude.

1974 Test Questions

The pre- and post-tests given to students in the second experiment are

presented here, beginning on pages .+1 and .+5 respectively (some of the

questions are specifically referred to in the text). All students in that

experiment worked the pretest, but only a few, who finished both the Logo and

Simper curricula, worked the posttest. The questions in these tests were drawn

from the same set used to construct the 1973 experiment's pretests and so

reflect their content as well.

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t ••~ut vitI> tho rl'Jhtl'l"",," n>r>" ..al ..n4 "'..~. tl'le t.<>t.a1 aq~a1 t¢ 10,. v"I" ...

2. 1<>01< et the n..>lt """..rd t<t th" lott. It 1 ... valu. 10 ho.. th..~ t~"~t 0:

t.~... n'.r;o,ol c" lt~ r1'lh~..."btuet Ito ....I~e e~"", t,,", toul. O.,I>"r>l1o •

..~-i ltoo ""\,,, ..... th~ toUI.

1. c-.....t1n"" wtth .~oP :1 <llItU there ..t.. no 100'0 '...........10.

,,~.t .10 yr." think tho no"t l ..tt..~ In thlo O"'1""nc. w1ll I>o?

....., "

~Ul \e, ~,~~ l>L.~" "Uh ..~.~ y"" 'l;l>I .... t~....~"~IM .1>O"t,1 <lo U, tt.·,t

~l.,,"· ,',! """"~"<' <.l>.. t,,<, "n""~ at tll_ ~H"O' h,'~ to tl><t pl.tc,,~ }'O\l

"1-\,,.. e~",· b.-l""l. A ..... 8 ..... C .....

..

1:"'3 >""'''111ht .t.l"U 10"". hon thr""" dO"ln .0 1:hey ""OU. Ue'!I'. l"'''leot.

Wl\l"h atat.",ont; 0" s"at;,.""nu ar.. ALW.\'!S !"IlUS "aq....dlu. oe h"", ttl. sUel'"

"r. """'&0'1, as 1",,'J ..,.. thq' .tHl .,.......

""!ll. ~ 111 .. n.

"'<;:1" B ,'31..... + 1eO d"".. " •••

....!l1& " d...,..u".." 0" ""..to ." an'll" B d.c on••

a.'ql. A d_....on " •• ""'11. Bin" .

• '1...1& B .. 180 dot<; _ ""'i1....

my 9J:":o.'dhthe.. lO<>Vad into • h.~"te<1 " U hte" }o-ld U v"",,,t,,•• , S

...." ..""'1"01& ..~ 32S bat... It.; " .....-1 ".,,10 t.o 1;oh., ellOy to 1";)< tor

"""k, a"" 3S bats U .... • ""1' .nd 11 " onu 1.,."" "od 4 """;>ir t."..n""

b ..ex 10'1:0 bo"", th"" hOlf c""y >e''''y ""t"" (nO't l,.c1"""l"'J <; ,dh;h"r)

....... letlo io "h.....Ul.,.

y.a lIo __._~1. 'I:Ot1l1 t.1:;?

/'• ..u the IlE;'ttlllf

?~~l1d?• yu 110

+.",.~~ . 'T""" ~""""

P\lt """'''Y 1'1 COin bolea:>.d ae" 1:01:01 to t.oo

I? ~c--------->

. "c~

U:I;J. .

"",b. """,ld 100 baa: 1'1 in orl"lna1 po..Juoo.

eorn"r e ..<>U!<1 b ....h.r. ""':'"'" f ..u.

""'..no,,'e ...ou:l4 be b.lev vl;..r. fae• .\9:;-.. "OIl ..

dOl; .."",1<1 ~ l.n t.tle pla.,~ ..lin ... i:.". e:;~tl '.."a.

th.. BOlli' fa"" 0: t.hI,. CUM, baa " 40~ On 1t. 110""'1."1. YOtl t""..ed the Cul><t

,,1.0<:""'10. :"",100 dll<1...... " around a" a"l. tl>ro",!b 1:ho polnto" ....,s II. t.to....

{.""'e d191ta e&ll Ju",'. mo... thon on...

aOlllld (e con 1>& l' or vj, .",1 .. IIlngl.,,,,

0'''' lI)·n.... II. au"oUtu"..... con."".....t a"""d tor 1I0Ct> dlq1t l.n a nu.lbar

u.ln9 U!~ Ubi. bd.........d tlul" puta _ ..18 bat..can t!>a ""o~..nta t.o

tor.. \lord.. 1'11.... ha Co""ec:U tM wor.d.....d thll '''''''~ ..1"h a atory.

•

•

'len> .... E. I, 0. U. V. X. Y.!1 (not 1'1 C:<:. SII, Til)

,

•

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J:. 0, }le;. G (hud •• 1'1 -CO:I~-). C (Med' •• 10 ~CAT-)

" ,., ,1"''''110'' t .. ,.c",.d t.1-..,t you bd Iourned t.he 0 ..191.. 111 "ube. lSO <!""1~ua t.IotH

U"',," In • """, U ..ot On ~... ""a t.hrO'~gh th.. e,,"ta... ot ,,~.. ta"... A<::O.i!

&n,s WI!I", ".,,<c on ....... ,,1. the"""111 t.h.. "ont.".. a of M;:;Cl ~",s !::>~r. 0'1:1 la.;

on >In ..d" "h"o'J<)h t.ho <:.nt..~. o~ CGl<l) ....d A6I"C. /l"" "he h u.. "lth th..

<lOt ..111 bo \lh ~." o"lqt"oUy.

to fa:;:; (S1) ~!la::..'1 (l)(lJ) lion.. (15). \;"hOn BUbO " ..o"a to r"",..",~..." M.

p~"". ""..." .... h. reedl. "ht M' dO'.l Sh"U1:' In.,,, "0 "h_ 00 1:.1<>;>1>0""

BH~ r_...... t· .... t.h.t.h. ,,<>4~ h:~ hC>'>. Mod..... ". To ....5'1 '" sec" we,"u,.

he livu nut d.,.,.. to .. l ..u"d..=H. IIhlt h Ma t>:>u•• n""l>qr?

Vdt... n·.....~er .. ltll at. le.,.~ t1.,.~ dl..1to In 1t. It"e ",".'''ph, "/Our pm~e

ou..booe. b1HMol', 0 .. loe>:•• <:o:;Un~t1cn) snd Un'" enbo"s &y.; ~o "eli"

"".d...:'lcll '~on~ lb. eh" n ......b... It y"u "en~, v... "~,,, ....!t.o ".,tue..

'to eo",~ee r"'u, ..",ds and tll. n.;"b.... 1., ... tory U,,, ",y 8ltbo clO" ...

n/90

««, .««««««««««««««(»»»»»»»»»»>>>>>>>>>>>>>>>>

h,,"" ...... ,,11 rooq,ulr_an""

an~ ar" n_ o:~ld"Uy

U"."s<d. 't.O PU"U"'$

... ""1'

««««««««««««««««««»»»>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

t.~o """a.. o~ " h",,~qo" au"d ""at... PUU> t.M pa"GCt. ..0 ~h ..qa hia oqu.:a

p>.rl<.1nq lCl" ..". 1;". 81 .'1uaro y••<l.. 1.. ".,a<t. Ba told p,,~~ t.h.......l<1nq

.."h .1<1. 0: U". po-oun.. 10.. "hru 1'...,<la 1""9<>" "111 =1:.. t.he "rO><t 81

"qua•• ~...d. ....,<1 ""'1' t.1I.. lot .'1"aro. bUI:; h .. "",,,'t. t"U P....!a h"" b1q "h"

lot. h n"". Vh ..t. h th.. -lot'. arM ",~.<l """ 10llq h 0..<:11- ,,11l<>?

ha.. ara :our U'iUru 1n b01<"o, pl .....u <l.ra.. ""a... 1''''~ th1"" t.1I.. nut

U;ur.. ''I' t.lI" r1o;ht n<>ul<! b.,

110.:>". Ie •••••• ~"'l"r...,••

t.h. Il.nto,,- "orr. ot ."qtn.au aro ."...,o.1no; r0e4 _19".' PrO'll ::"r1.

C:"n.'01 t.o "..., So..d 1. 150 "11,,,. (.a",o " ... Uk••U .......1'0. ,.11..0. thoy •••

_nur"" 1" til.. 0."". <It.,,euo.. l. t.oo tort" C......l 't.O 'I\o~. sp• .,,,,,,,,,,t t.

90 "11,,,~. el>l..~ .:>;;In~. Chrr 1<""",. that only o~ t.h.. ~oU""'I"9

Uv. "t.H","o"t" ::lUst bo tru". but ,h~ 1\"" to....o Mel> <1O". Cl:<el.

"'h" "tH""'."t ..~I"h YOII vo\ll~ re"o".....,,<I.

1. tlla <l18U,,"" t""", a"". S"n<l to Phobo. sp.".....~ 1.* 60 .11....

z. :OU~ t1.."n" t.h.. ~Ut" ..,,:.. ~r"", ~".h en""l to It'''' ....... "'iua.h _I;"" to1.."...

th" 1l1llt."""" trD1l £"rl0 C""al "'" Phol>o" Sp.=:ort.

,. tl\ .. ~I.U""", fr"," Red Sen::! to Ph.obo.. sp.e"per. 1,a 2«0 "H=o...

4. th.. d1= .... ""'" troo ten.. C..."l to /1.0<1 S"<I<l 1. :JD .11...... Ib:>r. thM

tw1ee ....... <lht.-ar_ ~."'" tod. c:n...l to 'hobo" Sp.e.port.

5, the dist""". ~r"'" red S"",,- to _'hobo. Sp""eport e""nOt b. da"...,,111od.

tt you c ... rot.. o.", t.n", leftll.."", e,,:,o •• "u",h u you pl""~", ""tell o!

th" =1><0.. On th" rtqht do you t.hlnl< t" t."" u,;e a. til... t ..ftl>a,,::! ="' ..?

th" :1g=o" in 'iro,,? 1 Mve _e..hUg in c:o=.Oft 'lob"... 1..~ a"...:'<:d. };-oJ

any ot I;hn tl'l"o-oo 1.... 'i=O"i' Z, e1"elo t.'!'... Usuro 1" sro"p ;\ t""...bo.lo"9-" 1n ..:=? ~ bot. f>O" In 9rollp 2,

Q>--.l-71" '9&1 t~_a aal .. l=re COlt. """ .1qht 'II..."tl Ion t.""e., 00 th,,1r

Ut.10 "t 0; ...... \to:> to 0;""'0" play..d ,

II

.d. l""'" .ay not b<>1tew" 1;11.1", but " "llo>t .)'0" look 11.... to _""_"e "Hh

Jl"r"Y "1st.....ho" ~..,u .O'...." th" "".h and C<I".O"a"U,

00 D6''';:-;>'''''' )"0'11 w"et .. ~""" tto. arlthoa'!:1" p..c:<lUCt Al'll...~d. U\~ "U$l>O_ yO'\O

r,,?h"'«l ... with Ale ."'4 .r~<i1."ed B vHl'Ill>:C. U c: h "ot. 8'1.,....1 to "":0.

vow~ts r::o';SO:;A:<tS

•• 5'l f1) 5J •• 8!].'.. .., hthe" .~

" l1! [2] L. fT;~:::J.., '",.,

.. f2j f2] y • r::J1l2J.. .... yo'

" 12] [2J " l2J-, ,.., .... ~ .. l2J., '0,

, ,I I

( 5 6 7

I I8910111113141S

I I I I I I I I<=001 OV."..,lqhl;. .......hel! ..h1'Oh abo h<>d .. ·...rro. ."pty eM on It. 'l:h<>

shelf l'oc"~ 111o;e.

:J"~ill~" th"";"'" .... II rol>ct "tr.; "an nail ~<l __ no. YO!JJ:' "U.lon

I" t.o "C",~le t::.. c:::>~s:"" 1:1 t?:.. bo",,,. IS, 12, '3 and 6. Ev"'l tho'-"'l1'l 1:1'1..

","!:en are l"·~lsJ.bl....191':. nO"~. yo" " ..n ~a'oI.r thh by relj'ln'il on YO""

•",,<>.:"-h="" PO'V":' lind ob"}'lr.9 U'.au ="""'1

I>"'t1"" 1n ttl.,."

!l<::>r oh.. thltllcol .h.. oh.;>wdk~ lut t11,.h" IlIICI ~.u~ • .",.. p<><;10tl ~== O"e

ot "h. "tel. """". aU> one ot th .. other t"", ".n_. 1>",,, _h" ",,-,,'I; r..,<te~

::<>= .=.. (sh.. ':"u1el nave C1re."od It). . "'h4t Ct;'...... tt.n "0.._ h ,,1\.;

~eh FreelO hu u• .., t:h. OIL",••:h ..l:: to otor. at" e,,,,. 0: "<it.,= and••tnc•

toll., potton h eolod..... tnth.. .0,,<1 odorleu lIke vUer. Ap!'lrodl. .. tose ..

probI"",_ Pleu. t1dp :her out, whleh 0:: tllus thrn Ute o! "I...>s. Mve tt...

......"it" <:=M'd. I by r ..,hdnq 1:1:.. 1>0>: " ....b.." " .."l;lon<:<1 In

It ""'" ..1'1:1\ 1;1'1'1; bolt n=1>,,, 01n". 3.

"'..nuo~e.f 1n "".....,,<1 1 til... atop.

Oth"""h" 9" ".el< to "<:=,,,,<1 1.

,.

,.

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11....."*1".. "~U":U :.:I f_~ by I; f ...~. """ _I" ot l>h C4Jl1h..~ wUl ~h"

Sbh.ot tu" t.o "101,, to ~"1~'iI wnh h1'" "h.. lIoxt. t>. «a"" ~o "'U1t?

U:"u " wu "ha~'O...s Into Uq>.>ro a by b'pl" "ul", "Iu.•• "hL",'O. C

~ ~:-....."'" ..ul" Itnd d...... th" .... ,,It. (1<;1"". DI

,600.. a t l)

..hot (\0 YC>Il think th" """1. ~_ lotUl::• .,., tha rl9ht lJ> thh ""'I""'"'''''.ho,,14 bltl

"Mt "ho.,ld the ,.."t hy l.~ta.. " 0" tho.. tatt be?

.h,.! p..u=,. in th.. Vt>l~od Stat..,. "u thl8 halI4 11.1»1=..10,,1. fo:1'

c:a=tu~lc ..uo~. $..,.....1 .....d. Will lo. Un".up"l1e'" 1>l"

.~ln<; ~l\. 1>a"d .1<;". On••ttor another) c:>. the """I. P4o;U. ,,<:>

I' -) D

~ -) OG

pIns.. ,...1<.. "" ,,0:...."ID. ot yo".. 0.." ..h1"'" "".. <:t."".... S\I,..lO.<.il 1"'0;0 ... ~,,~ ....

and ._ 1'1"" ~h"Y ""..I<.

If L"\<;Il.. II o~ "'''9"1 .. h ~.._ tle.... •• big .. an ..l. ii. an" an..l. C I-

20 dog..""a 1>1 than angl" P. hen< bl'1 I" anil. iI?

tz.... It1..t .. Meh Of loll. thr.. t!nqeto!'.l1od l.u.....",!11~""~. 1>..1""

'''''''' an 1t"0;11.." _rl.

,,"

flu.. <lc .... Un... b.t...... ncll 0= tho thl"~. 0<1 t.hoI 1.n "".I tho<

l,,"~'l""'Ju 0" t.h. tl~ht. 1" ..h1Ch O:II.y Ada" '''''.1111n~.

Yo"r ..lut"" 10 t.o "rit." a ra",",ulva J.o.jo p...,c"dur...;>1"" "Ul "olp t""

col"",\, "'''p:",l"eo to>, .."ny 'i"aaraUou. Yo".. r=oc4o<1"..a al\OlJ.14 p.l"t. "'I,,;

tha colo:>y 1001<. U~'" ",,4 thon. :t.~ t~...... aro 1.." th.... J b111 ....""A1n:r.~

1n t.... ""10ny (u~. CO:J;1lr. Pa~t. S) .It ahO"ld <11". a" yo"r pro"<lJ"" C.n

prlnt -J!X1INcrIO:>II- .nil '01 CO-Mr. o,",-rw~"'" 1t. .t.<»J1J .011..... th.... J

""Un9 ",uha to ·<1",,1<1. WM~ t.h...."t g"nacAtlon ·ot ..... colo.~y h ""4 t.I\...~

cdl up .. broth,,: to hnn41. t"at nn eol_:(1

uu. Th. "",ly ltyln9 etut...,...0'1 til. plnnat

"In~.. call ~h....aolyu ·l>.lQlt.·. " colon\, ot

thol. Uta '!<,~..a 10<>Ka d"capt.1 Y .ly 11~" •

Un" ,,~ 'Ur,,_ a"d onu, _~<>r ""....plo. ,0010H.

"'~U."

t. ~

$1 "eM"..

6~.t 1nt..crc"t... "

Sl"'~.......'"b1"~

6;J(>~~O

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"'~""'t,:pr P

"'::'lcl> <10 wl>u'1' ••••••••••••••

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}."" ....y?). ;>leUG ""pl"ln t." ..a vh"t. t.h" word ·GA."llM,f- .Hn. or .t••u9<J

t.'r••"d wll•• t.!'>o,,~ oUly "",d.a acO<oI".4 1t. .... ..,. 1n thh d~.1':1t.1"" o~ ..

.)

,)

It th" Ural l>1(l1t U "t. th"" t.1» n ..... 3 1>1;1" <I~" ...~.:l .. " ....

bl91tB ·'011· Ara toorn lIt tha >,1<;1<t..1>4 o~ u." c:Olony. ~. It

f.h" colony I. 1000t, f.ne.. tl>O na"t. g"".....tJ.cn .t. 0110,111.

If th.. tlnt tll'ilt. .IS III 0, t.1>"" tl'.. t.t.eo, J b19Ua cU......d 1 a ....

bl~lU ·O~- ..,,,, ~rn at ti.e n,;-lI.t a"<1 ot th. c<>10"1. :.0. 1t tM

""l""y h 011011. t.hell tho aul; ,>""":,,;.to,, .t. 0'100.

n tto" U .."t. )1'i1t. 1. 'lot. .. ° ""'d not. • I. U._ 1'....... ,,<"0"".:1...,..O1'>ould p~1nt. -A.f..Ull t.I~: POR"- "M. b<> <10<>;"

III>"t """",,,,,1 ...."ld you lil,... to ..a",. ~o obay II:>? ., ••••••••••••••••••••••

.1.11110 Wh"t do•• thls 51o:p." prO<l....... dO? ••••••••••••••••••••••••••••••••

MIt,ll, (=15:ro A X1111t.,II, XIWL /I. XIWL A X~..PUT P zor

h? .

_BtIlAA 10001'000101101101101)O~GG

'""UTI~CTIC:'1

c:; any ft." 0""", if y<''' ._ t.hoIl:; ddblt1o.... 1'0" Can t.::f 0\Jt. your

B:u;"AA ...~y u .... }'Ou """.. ~ "oe Ch.. ...,.... "t...... AinU ~ .~l:; ..11 l:;~"

<leeldon" ..ach IlIlOA.'1. bro~h ..r c".t ",.1< d Ch.. or4tr.. I" ..M"a ho ",Ut ....".

Ilrlt.. a al>o"'t pr",,"'."" thu "Ill l ..t. .... t.YfM t.l-.o ........" ....1. 0'" tha l.:t. .....

....li:.. Il.:l.":>-,, ..U"I; t:l>e ... tchlnIT :c:u"lt..

PIIT A ,sro A 100PIIT A 905;;0 A Zp;n /I. "SCo;! A (KOa,;)CC1I A ZI\O?,~

A!Y.l' A 100'Ill P KOillC

O~876S4nl

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001 IPIl't 8 6~

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OO~ .c..." C (OilD)

100 .2 (Iool

1. 1t. • (\lM:UO"7 ••••

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d,.. ' ..r any 1J>p"t. ....:<1. yo" e.." un .."y o~h,,, F.o<:a<!"..u yo,,·... a ..rln."

• t.u~y I( y"" .11"" t.h.l .. <I"Un1uon.. A• ..0""1. t.har. 1. "0". t.h"" Or.a

...y to do H. PlUM """'" .11 t.h. ""y" you t.hlnK It. eM w dona.

6",,;>0"" yo"'",, p\lt lIilColla. Int. t""..•• ·_0<)'. Vh.ot, ..111 t<>Jo a.y It yo..

tn'.' P W/l,,>lG -~:I:'latR~

•

Page 135

Appendix 3 Sample Curricula

The following pages are excerpted from the Logo and Simper curricula used

in the second (1974) experiment. The emphasis on and ordering of topics

differs from that for the first (1973) experiment, but many of the problems and

examples remain the same. The Logo curriculum begins on page 136 and is

presented almost in entirety from Part 3 on, excerpts from the Simper

curriculum begin on page 152.

t.""l''' print. 5 ....1 tll.." l'nnto,p.~[,;r CAll'" BE US~:l AS ~Il I,,;>tJf.:t1 O()~:l 1101." RU1lF." .. ~...Ltl2.

1.0<]0 pd... ts " ", 8noJ 1<1' ...., yO" ty;>oJ8.,..,"thl.n'). it p"'ln~" ..Mt y0" ";{1''''10

tGo)o Ilr!nu "'),\11 but .~n "'y.,ny. 3 IS All ElCT~" Illi'll:r.

Logo punto HELU)

1.<>;;0 P:1nt'"TaU,E .IS 1 III~t..r ,USS[~~ POA Pi<im'.

:LO'J0 pr1"'" REOU;:ST

:Log;' ....1tl.. 10

1.090 pr in I:e B

tOO3O print. XYZ. IlEECS l'IEA..n~'O_

" ·IIELLo- .~ t<X;Q S!:;U:;C;lt.·

·25- m .:rO~"456

123~BC ·P....tJ:- 5~.7

·.5· TI.~E

-I'.AlI.T -, .'1)~)))9~~~)~~9~)~n)~))))

tn 1.090. tll"u u" tW<l 1<1noh O( Ith!".. ta. ( ..) ""'1""n".. ot

typ.......u.r ""..<.~t"u 8".l'<"uncl.~ ~ .. -1'..1.. o! d".,bh q~O"" OIUl<. (·1. on.d

(b) 1"t<>9"u ("OIJntln'l '1=1><1<8 11>< -t, c', " ~••• ,1 ..111"11 <!o "",t.

" .."d quot..... Ph.•"" c:trd.. th.. it b.1_ u~lc:~ you tn:nl< ....... 11t.."o1.:

p:nllT XY":

&...... 1'''''1'10> ~,,_ pt"'ur,," or box,," to .t.ono1 tor e.....~~a"<l8 1n

1'ln'!"a1..3 11)<;.. 1."10. Any Input....~01 OU'I;p·:t........ -:: "" <l'; <l.re·~G p"1"~""

t""'sl"o;l box". :or ..h1<:h "I\d... ·vd"~$ ~r" In?"t:i ""-<1 a y tr"" .x..><.... ! ......

..M<:l1 th.l... v.lo,.... a .... b ..ln7 ....t<'...n~l (o"tp"to). ~011<:....... t <lac:... t.<>..

bol"'" o1oe", anof. "<y 0'" 'M' new ·<""'''''''1" ",.')~() """ SUIl. 1.l }'O'J ..1. ...".

<:h..=k th" 'H,,')''''''':

':ry tll.. 1."'9'0~ ...~. 1ft th.. left cot"'-"II> boot......~cl. <1r....... U,n..

1><It......... each "<><:n. _«'I ano:1 th........"t. 1. p..odu"... On t.h" U ..h\:.

FIUIl? $!I:l <l? 3 Al'l) S

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"

"

Appendix 4 Student Programs

The following are listings of some original student efforts in Logo and

Simper. Some work and some have bugs. They are here to indicate the kinds

. of programs that interest students at various stages in their learning of

programming.

TO BEGREAT1 PRINT :,. . . "2 PRINr """',"""6""""'THIS IS GREATNESS •••3 PRINT

• ••+6 ••••••••••••*••••*.**••*.*.***.************************••***••**.**.4 PRINT·····,1111,',1""',1,',1,··**···',1,',"'·*··***"'"I**.'II"'~**** ••*"

5 PRINT·····,"~//111/1//1,',11111***····"",',',·***.*·,"""*"""'~.*****."

6 PRlt\T··········*···,"'11,·*········*·,11,',1,'****···"11#·,11*1"',*•••••*."

7 PRINT····**···*···*"""'*****·**•••·"""81,•••***·"",*11,.,",'.**••••••

8 PRINT···~··***·*···IIII',I***·*·***·**""',I",.····*·,I',,·*'**1',',*···***··

9 PRINr··············,11,",··*****•••*.,"'#",,***.·**"',' .*.**"",***••*.*.10 PRIm'-·*··"111,·**111111,···***····**1'61111"*****·*",,,***.*"",********

11 PRINT _..··**"""···'1""'*···*·*****·""'81"*******1""·****"",.**•••**12 PRI~'l'ft*···;"'I'···"""'*•••••••••**"""",*••••••"",.**••,,,,,**.*****_

13 PRINT···**/161',"11111111**··**·*****,"',',1,.*******"".****1",'••••**••

14 PRIN-r···~·",I'#',llilll"··**·**.**··'HII*',I#**** ••*IIII'·••**1""***·***.·

15 PRINT•••••••••••••••••••*••••••**•••••••••••••••*****••*.******•••*••****••**.

~~ :~i~ :;:~~ ~~i~i ::::~:::~~~~=,~~~~~TI~~i~~~TION BROUGHT TO YOU By••• •20 PH.INr ·THIS PR03AM. WILL SELF-DESTRUCT IN FIVE SECONDS.·21 WAIT 522 PRIN1' -1111111 I II III J 1J I U 111BOOOOOOOOOMMMIlIt Illllflllllllllll111l"23 GOODBYEEND

_.BEGREAT

THIS IS GREATNESS •••**•••**••*******••••••••••••*********••••*******************.*.*.***.**•••• ***••** ******* *.. .*.***.*..... • ••••** *.**.*. * **.*••**•••• *~.*••.jl..* ••*****.....* *••*.** *. **.*****••••*••****.. ..****••• ~*. *******.. ****•••*••*.*****••** ***•••••*.** .*...*..... *. *.******••••••••••••• .'lIo*********. .*.**** ****. • ••••**.•••• *.. *••**•••••** •••••** *••** **********.* ••• **••****.*.. **••*** ••*** *.**••••••*. ..* ..*••••*.*** .**.... **... .*.*•••*•••• *••••*.***.. **••*** *'*••* **••**.*•••• ****••* ***.* ********••*......**••*••••*•••***••••*.**•••**••••**•••**.**.*.***.**.*••••••***

(TrlIS SECRET INFORMATION BROUGHT TO YOU BY, ••JIM INGLIS)

TRIS PROGAM WILL SELF-DESTRUCT IN FIVE SECONDS.1I1111II111 111II1 11I11 BOOOOOOOOOMMMIIIIIIIIIIIIIIIIIIIIIIIII

GOODBYE

_TO STARTRBK85 PRINt YOU ARB CAPTAIN KIRK OF THE STARSHIp ENTERfRISE•••• Il'·S PIVE

810Y~~~NT ·'MISSION t TO EXPLORe STRANGE NEW WORLDS ••• TO S££~ OUT ~EWLIFE·

'15 PRINT ·NAND NEW CIVILIZATIONS••••• •820 PRINT ·UII",',',TO BOLDLY GO WHERE NO HAN HAS GONE BEFOREI·825 PRINT ftAPROACHING GAMMA FOUR t CAPTAIN·830 WAIT 2832 PRINT "I EXPECT THIS TO BE A NICE SHORE LEAVE·935 WAIT 2@37 PRINT ·CAPTAINI THERE·S A KLINGON VESSEL POLLOWING USIl045 TEST IS REQUEST ·REVERSE COURSE·850IFTRUE WAIT 3851 IFTRUE PRINT ·REVERSING COURSE·852 GOTOLINE70955 U'FALSE TEST IS REQUEST ·OPEN A CHANNEL TO THE KLIHGON VESSEL860 IFTRUE WAIT 4@63 IFTRUE PRINT ·HAILING FREQUENCIES OPEN , SIR-e'" ~ IFTRUE REQUEST.. •1)70 IF~'ALSE TEST IS REQUEST LOCK PHAZERS ON TARGET@75 IFTRUE WAIT 3677 IF'l'RUE PRINT ·PHAZERS LOCKED ON., TARGET _ SIR-

::~ i~i~;:Ep:~NT ft WHAT NOW SIR·@95 PRINT "'SHOULD I WAIT FOR ORDERS TO FIRE?·8105 TESTIS REQUEST ·YES"'110 IFTRUEREQUEST@115 IFFALSE PRItIT ·FIRll~G PHAZERS·8120' IFFALSE WAIT 50122 IFFALSE PRINT -GOfiEMII-8125 IFFALSE i:RINT "ONE WARP ENGINE DEAD CAPTAIN t THE KLINGON SHIP IS

HELPLESS8130 PRINT "FIRINGPHAZERS8135 WAIT 5@131 PRINT ·GOT·EM·8140 PRINT' ·THE KLINGON SHIP IS DEAD CAPTAIN·!tENDSTARTTREK DEFINED....STARTREKYOU ARE CAPTAIN KIRK OF THE STARSRIP ENTERPRISE••••IT~S FIVE YE~R

MISSION. TO EXPLORE STRANGE NEW WORLDS •••TO SEEK OUT NEW 'LIFEAND NEW CIVILIZATIONS•••••

TO BOLDLY GO WHERE NO MAN HAS GONE BEPOREIAPROACHING GAMMA FOUR • CAPTAINI EXPECT THIS TO BE A NICE SHORE LEAVECAPTAIN I THERE·S A KLINGON VESSEL FOLLOWING USII"EB"END

SHOULD I WAIT FOR ORDERS TO FIREE?"NOFIRING PHAZERSGOT· EM! !ONE WARP ENGINE DEAD CAPTAIN t THE KLINGON SHIP IS HELPLESSFIRING PHAZERSGOT·EMTHE KLINGON SHIP Is DEAD CAPTAIN_GOODBYE . .

001 ;PUT A 10002 :IOT A 86003 :PUT A 12004 :IOT A 86005 ;PUT A 12006 ;IOT A 86)07 ;PUT A 1008 rIOT A 86

009 ;PUT A 4010 :IOT A 86011 :PUT A 10012 ;Iar A 86013 ;PUT A, 12014 ;10'1' A 8&015 :PUT A 10016 ;IOT A 86017 ;PUT A 12018 :10'1' A 86019 ;PtJT A 10020 ,lOT A 86

,- 021 :PUT A 13)22 :IOT A 86

023 :PUT A 10024 ; lOT A 86025 :PUT A 12026 ;101' A 86027 :PUT A1a

028 :Iar A 86029 :PUT A 12030 ;IOT A 86031 :PUT A 10032 :IOT A 86033 :PUT A 13034 :10'1' A 86

035 :PUT A 10036 :10'1' A 86037 :PUT A 12038 :10'1' A 86039 ;PUT A 10040 ,lOT A 86041" ;PUT A 12042 :IOT A "86043 :PUT A 10044 riOT A 86045 :PUT A 13046 :IOT A 86147 :PUT A 10.,)48 :IOT A 86049 IPUT A 12050 :IO'I' A 86051 ;PU1' A 10052 IIOT A 86053 IPUT A 12054 :10'1' A 86055 :PUT A 10056 :10'1' A 86 "

057 :PUl' A 10058 :IOT A 86059 :PUT A'12060 :IOT A 86061 :PUT A 10062 IIOT A 86063 ;PUT A 12064 :IOT A 86065 :PUT A 10066 rIOT A 86

067 :PUT A 12068 :IOT A.S6069 :PUT A 10070 ;Iar A 86071 ;PUT A 10072 IIOT A 86)73 ;PUT A 13

074 ;PUT A 13075 ,Iar A 100076 :PUT A 12

086 :90

001 ;PUT C 4002 ;IOT C003 :PUT A 10004 ;PUT B 12005 :ASK C006 ,5'1'0 C 110007 slOT A 110

OOB :ASK A009 :5TO A 120010 ;IOT B 120011 :PUT C 0

012 slOT C •013 :PUT p 1014 :PUT C 1015 ;IOT C ;.

016 :HAL017 ,PUT P 14

110 ,400

120 :180

001 ;PUT A 20002 :IOT A 154003 ;PUT A 1004 :IOT A 100005 ;PUT A 201006 :5'1'0 A 199

007 ;PUT A 0008 :5'1'0 A 200009 :LOA B 199 (PICK)

010 :RAN AQ1'! IS'!! A R~

012 :5'1'0 A 8B013 :INC B014 :RAN A015 :SHI A R8016 ;5'1'0 A is017 :INC B)18 :5'1'0 B 199019 :LOA B 200020 :LOh' A 200021 :INC A022 ;5'1'0 A 200023 :JUM B LINE024 : PUT P PICK025 :PUT A 2 (LINE)026 :5'1'0 A195027 :LOA B 200028 :SUB B 197029 :LOA A.199030 :5U8 A 199031 :PUT C 5032 ;IOT C 100)33 :PUT C 25

034 :Iar C fA035 ;JUH B .+2036 : PUT P PICt<

037 :PUT C 4038:10'1' C 100039 :SUB A 196040 :PUT C 25041 ,lOT C @A

042 :LOA C 198043 ,ADD C 196044 sSTO C 196045 :PUT P LINE+)

150 :324151 IPUT A 18 (STOP)152 :10'1' A 100153 ;HAL

154 :25

_TO TUTE.,0 PRINT "TlTO.POZA.JR.·.ENDTOTE DEFINED_ TUTETI'l'O.POZA.JR.

i~~ ~~~Nr"MARY.JO.POZA.".ENDMOM DEFINED

i;~ ~~~NT "FAUSTO.POZA.SR.".ENDDAD DEFINED

TO ME"0 PRINT ·KAREN.S.POZA.·tENDME DEFINED

iig ;i~; "LUIS.H.POZA..ENDBIRDS DEFINED

ii~ .~~i:iH2QUINCHa".ENDQUINCHO DEFINED_TO US810 DAD&20 HOM830 ME840 'l'UTE'50 BIRDStENDOS-DEFINED_USFAUS'l'O.POZA.SR.HARY.JO.,PQZA.KAREN.S~POZA.

'lITO. POZA. JR.LUIS.H.POZA.

TO FOUR; IP;810 RETURN TKO SF ;IP;IENDM.FOUR DEFINED

P FOUR "TRAIN"I

TO FIVE t INPt810 RETURN FOUR BF :INP;08"0FPIVE DEFINED

P FIVE "RETURN·R_EDIT FIVE@EDL 10'0 RETURN BF FOUR : INP.END

~;V;I~f~~URN·

_P FIVE "MONOLCGUE"

_LIST FIVE

TO FIVE :INP;10 RETURN BUTFIRST POUR : INP:END

_EDIT FIVE8EDL 1010 RETURN FOUR BUT:E'IRST :IMP;.END

F;V:I~:F!~OLOGUE"L_TO ST.36:PL:01 a RETUR..~ WORD woRD WORD WORD WORD

L ;PL: TRD ;PL;tENDST.36 DEFINED_P 5'1'.36 "SEASON"SESONA

TO JKL1 BELL11 BELL111 BELL1111 BELL11111 PRINT "HA,HA,ALEX1·11119 JKLENO

F :PL: SEC :PL: FOUR ;2Ll FIVE :PL:

TO PAY

~g ::i:i :::::::::~::::::~::~~#~:~'~~~:~!:':~~~~~~~*~::~!MAY 4,2000·30 PRINT """6""t','##1", WE DEMAND TOPLESS CHEERLEADERS""""'"40 PRINT "THE HotTEST STORY OF THE WEEK IS THE STORY OF THE rOPLESS

CHEERLFADERS. THE TERJ~N BOY REQUESTED THAT THE CHEERLEADER DETOPLESS WHEN PEFORMING AT A GAME. THEY COMPLAIN THAI' 'litE GIRLStlNIFORM. WERE FLOA'rING OVER THEIR K..'1EES. THEY SAID THIS WAS BECAUSETHE CHEERLEADERS WERE FLAT CHESTED GIRLS. TREY ALSO SAID THECHEERLEADERS UNIFORM WERE ALWAYS LONG. SO THEY DEMAND TOPLESSCHEERLEADERS. THEY SAID THAT THE OFFICIALS (OLDMEN) DID NOT CHOSE THERIGHT KIND OF GIRLS FOR CHEERLEADERS. THEY SAID THAT THEY BE ALLOW TO

. 50 ;~~~i ~E~~~:A~i~~;A~~~ST~ETOPLESS CHEERLEADERS. THE SCHOOLBOARD CHOSE 200 BOYS FROM CERTAIN CLASSES (HOI1E ECONOMICS). THESE ARETHE RE 50LTS;#',#II'##I"OI,Ol"il##,#',IIOI'6#'#6#####I"'""',lliN,,,"," ",#,##"Q",,#IIU#II,B#dl'HU"',H,HH##NIK#HHdNU###H#1,##'""'INI##I# "6111 6'# DO WE NEBDTOPLESS CHEERLEAD~RS? ALL THE ~OYS

SAID YES. SHOULD THE BOYS BE' ALLOW TO JUDGE OR PICK THEIR OWNCHEERLEADERS? ALL SAIDYES.I#I##HUI"II""1'6111I"HH"I"III"HI'HUHUHNUDII",u",a",##,#U", THE GIRLA WERE ASK WHAT THEY THOUGHT ABOUT THa IDEA? SHAao~

SHAFER: I TnIN~ IT IS A GOOD IDEA. ELIXA WEON; I BErT~R OReEK SOME OfTHOSE MARD EDEtl' FOR BIGGER AND ATTRACIVE BREAST. 'EERESE BLANCH:WONDERFULII '1ERY WONDERFUL I I ANOTHER ,POOL WAS -TAKEN WITH THE MENTEACHERS. THIS IS HTEIR kESULTS; MR. VERNON: I COACH EvERY GAME FREE.MR. TROLl; I BETTER BUY ME A SUPER DUPER WAY our CAMERA. THERE WE~E

NOT VERY MUCH REACTION FROM THE WOMEN. aUT THEY LIKZ THE IuEA VERYMUCH so THEY THOUGHT TnEY BECOME CIiEERLEADERS (FOR THE SENORCITIZENS)"

END

TO FIG ;N: :GUESS,5 TESl' IS IN: :GUESS:10 IFfRUE PRINT -IF YOU THINK YOUR SO SMART WHY DON'T YOU TRY

TO EGG10 PRINT ·WELCOME TQ E~. WOULD YOU CARE FOR THE RULES?·20 TEST IS REQUEST YES21 IFTRUE PRINT "I AM GOING TO RANDOMLY CHOOSE A NUMBER BETWEEN 1 AND 1000t~~O YOU WILL HAVE 10 CHANCES TO GUESS MY NUMBER. BUT TO HAKE IT eASIERFOR yOU I WILL GIVE YOU THE FOLLOWING HINTS, GUESS HIGHER,GUESS ~OWERAND

IF yOU ME SUCCESSFUL I WIL.L REWARD YOU WITH A FOR'l'UNE.·22 IFTRUE FIG ~~D 1 1000 REQUEST23 IFFALSE FIG RAND 1 1000 REQUEST24 ENDEND

"''l'HIS IS DRAW,IT WILL DRAW It i'IGURE WITH ANY NUMBER OF SlD&S 'l'HATYOU WANT. HOW MANY 00 Y:JU WANn·

TOE1 PENUP2 ASETXY ( - 200 ) ( ~ 200 l6 PENDOWN1 0 MAKE ·x W REQUEST12 IF ZEROP IXI 'l'HEN DONE ELSE A IXI tXIEND

TO A IX: :Y:10 TEST ZEROP tXI12 IFrRUE J)

14 IFFALsg FRONT QUOTIENT 1200 IYI16 IFFALSE LEFT QUOTIENT 360 IYI18 IFFALSE A DIFFERENCE IXI 1 IYIEND

oro CRAP :XI5 TEST ZEROP IXI7 IFTRUE DONE10 IFFALSE PENUP15 IFFALSE BACK 5020 tFFALSE SHOWSNAP 125 IFFALSE CRAP DIFFERENCE :X. 1END

oro 'rP2 WIPE3 CLFARS PENUP6 PRoNT 20010 PRINT "HOW MANY TP'S DO YOU WANT?"'5 ZEND

TO Z10 MAKE ·X·REQUEST25 tF ZEROP IX. THEN DONE ELSE CltAP IXIEND

'l'P.DRAW2 WIPE3 CLEAR10 PaINT

15 EEND

TO 010 PRINT "'AIN'T If B~U'l'IPUL?· • ..12 IF IS REQUEST YES THEN PRINT.WELL,THANK YOU VERY MUCH. ELSE PRINT •

! WOULD LIKE TO SEE YOU DO SETTER TOOTS14 PRINT °00 YOO WX~H Tg TRY AGAIN?16 TEST ISREQUBST YES18 IFl'RUE WIPE20 IFTRUE CLEAR22 IFl'RUE PRINT ·GOOD,HOW MANY SIDES DO yOU WANT?·24 IFTRUE E26 IFFALSE PRINT ·GOODBYE"END

TO RECTANGLE IL: :WI tCI5 IF GREATERP aCI 1 THEN DOl10 FRON'!' :L:20 RIGHT 9030 FRoN-r· IWt45 RIGHT 9050 RECTANGLE ILl IWI SUM IC,END

TO RECTANGLE ILl IVI10 FRONT ILl20 RIGHT 9030 FRONT IW:40 SENTENCE • 045 RIGHT 9050 SENTENCE =SENTENCE ~ 160 IF SENTENCE • 2 THEN 8070 RECTANGLE :LI tWa80 ENDEND

TO RECTANGLE :LI tWI10 FRONT aLI20 RIGHT 9030 FRONT ,W:40 0 <l X45 RIGHT 90SO X "" X + 160 IF X a 2 THEN BO70 RECTANGLE tLI IWI60 ENDEND

~~~~~DN~~:~~; ..NUMBER AND SECOND NUMBER

AGAI~ ••• 00 ••••••••••••••••• 0.' 0 •••• 0 •••••••• 0 ••••• , •••• • • •••• •• •• • •••• ••• "

......................................... 1111 Illllllllllllllll15 TEST GREATERP rGUESSI ;N:20 IFtRUE PRI~l' -GUESS LOWER"

~~ ~~i;~S§W~~~Nis"~g~~SN~i~H~~;SS?·35 TEST GREATER? :N: :GUESS~

40 IFrRUE PRIN~ "GUESS HIGHER"45 If"fALSE PRINT "GUESS LOWER"50 n-;"R\JS FIG RAND 1 1 000 REQUESTSS IF'FALSE FIG RAND 1 1000 REQUESTEND

i~~ ~B"WHAT IS '{OUR@20 P ~WHAT IS YOUR~ 30 P SUM OF' FIRSTIittlDAM DEFINED_AS""H,.\T IS YOUR FIRST NUMBER?WhAT Is YOUR SECOND NUMBER?~UMBErt NEEDS A MEANING.I WAS AT LINE 30 IN AB_TO AC • •ij 10 PRINT WHAT IS YOUR FIRST NOMnER?

:2~ w~~~i i~RY~~:S;E~g~~UMBER?WHAT IS YOUR SECOND NUMBER?i WAIT FOR SECO~ NUMBERFOR t,EEDS A .!'tEAMING.@P SUM OF FIRST NUMBER AND SECOND NUMBERNU~BER NEEDS A MEANING.@nwAC DEFINED_ACWHAT IS YOUR FIRST NUMBER?FOR NEEDS A MEANING.I WAS AT LINE 20 IN AC_12LINE 12 OF WHAT PROCEDURE_'2 Is MY FIRST NUMBERLINE 12 OF WIIAT PROCEDURE?

TO PONG10 HAKE ..~. SO11 lo'.AKE " " ( - SO12 "'J\.KE "0" SO

~~ ~~~ :~~,,(O- SO15 ~IAKE "S2" 020 WIPESNAPS30 BOUNDERIES40 PADlJLE45 SCORING47 WIPE55 SHOWS NAP 260 START80 CHECKEND

TO BOUNDERIES3 SN.:..P 24 PENUP6 ASETXY ( - 400 ) ( - 350 )7 PEN-DOWN9 FRONT 80012 LEFT 9015 FRONT 7001 B LEE'l' 9021 FRWT 80024 LEI:"T 9027 FRONT 70030 ENDSNAPEND

TO PADDLE1 SNAP 15 FRONT 107 LEfT 909 FROt-i-T 7011 LE~'T 9013 :moNT 1015 LEfT 9017 FRONT 7019 ENDSNAPEND

TO SCORING1 SNAP 32 FRONT 503 LEFT 904 FRONT 1005 LEFl' 906 FRONT 507 LEFT 908 FRONT 1009 ENDSNAP10 SNAP 511 FRONT 2412 LEfT 18013 FRONT 1214 RIGHT 9015 FRO~T 10016 LEFT 13517 FRONT 2S18 ENDSNAP19 SNAP 6

20 FRONT SO21 LEF'I' 18022 FRONT 5023 RIGHT 13524 FRONT 5025 LEF'l' 4526 FRONT 7S27 LEFT 9028 FRONT 4029 LEFT 4530 1:'RONT 1031 ENDSNAP32 SNAP 733 FRONT 5034 LEFT 9035 FRONT 5036 LE~"1' 9037 FRONT 3638 LEFT 18039 FRONT 3540 LE1:''1' 9041 FRONT 5042 LEFT 9043 FRONT so44 ENDSNAP45 SNAP 846 PEtmp47 FRONT 5048 PENDOWN49 LEFT 9050 FRONT 10051 LEFT lao52 FRONT 5053 LEFT 9054 FRONT 2555 LEFT 18056 FRONT 7557 RIGHT 9058 FRONT 5059 ENDSNAP60 SNAP 961 FRONT 5062 LEF'l' 9063 FRONT· 5064 LEFT 9065 FRONT 5066 RIGHT 9067 FRONT 5068 RIGHT 9069 FRONT 5070 ENDSNAP71 SNAP 1072 LEFT 9073 FRONT 10074 LEFT' 18075 FRONT 5076 LEFT 9077 FRONT 5078 RIGHT 9079 FRONT 5080 RIGHT 9081 FRONT 5082 ENDSNAP83 SNAP 1184 PENUP85 FRONT S~1

86 PENDOWN97 LEFT 9088 FRONT 100&9 LEFT 9090 FRON'! 5091· ENDSNAP92 SNAP 1293 FRONT 5094 LEFT 9095 l"RONT 10096 tEl''T 9097 FRONT 5098 LEFT 9099 FRONT 100100 LEFT 1801 01 FRONT 50102 RIGHT ,90103 FRONT 501 04 ENDSNAP105 SNAP 13106 PENUP107 FRONT 50108 L£1:'T 90109 PENDOWN110 FRONT 100111 LEFT 90112,'FRONT 50113 LEFT 90114 FRONT so115 LEFT 90116 FRONT 50117 nlOSNAPf:ND

.':1.'0 START2 UNPOKE3 PENUP4 MAKE "Yl" ( - 1 )5 MAKE "Y2" ( - 1 ) •6 IG~ORE fUTSNAP'.' 1 1 2- "350 0 -350 O·"I MAKE "X 0a MAKE· "Y" a9 MAKE.'"JtX" WORD FIND RAND 1 2 -t --..so10 HAKE. DY" WORD .FIND RAND 1 2 + - 3011 WRAP "-400 400" "-350 350"12 SHOWSNAP 213 SCOREP lSi,14 SCORE .S2115 CLEAR

. END

'1'0 CHECK1 MOVE ASKCHAR 03 CLEAR~ WALLHIT6 MOVE ASKCHAR a7 IF EITHER LESSP IX, ( - 349 ) GREATERP .Xz 349 THEN PADDLEHIT10 RSETXY 'ox, tDYa11 MOVE ASKCHAR a12 MAKE :Y: SUM I¥t ,DV,20 MAKE X SUM ,X, 'ox,40 CHECKEND

TO FIND ;NOI ;YESI2 IF EQUALP INO: 1 THEN RETURN FIRST ,YES; ELSE RETU~~ ~~ND DIF~E~~C& :N~:

t &UTFIRST IYES:END

TO SCOREP IRI1 IF ZEROP ;R; THEN IGNORE PUTSNAP ·3 4· ·,50 300·2 IF EQUALP ;RI , THEN IGNORE PUTSNAP "5 •••'.' .::'~5g0 ~3g0g0.:4 IF EQUALP IR I 2 THEN lGi~ORE PUTSNAP :.6

76 IF EQUALP ;RI 3 THEN IGNORE PUTSNAPa IF EQUALP :R; 4 THEN IGNORE PUTSNAP 8•••••••••151°5033°0°0•••10 IF EQUALP sR: 5 THEN IGNORE PUTSNAP .12 IF EQUALP IR: 6 THEN IGNORE PUTSNAP .10 4••150300.14 IF EQUALP ;R, 7 THEN IGNORE PUTSNAP 11 4 150 30016 IF EQUALP ,R; 8 THEN IGNORE PUTSNAP :"32 .4: :,'550° 330000:18 IF EQUALP ;R: 9 T.dEN IGNORE PUTSNAP

~~ ~~ igg:i:: ::: ~g ~: ~ii;St,lI,lPSEND

~OI;C~~:O~O:OI THEN IGNORE PUTSNAP ·3 3· .1-150) 300·.2 IF EQUALP :0: 1 THEN IGNORE PUTSNAP "5 3 -150 300

4 IF EQUALP :0: 2 THEN IGNORE PUTSNAP :'867 ~3.: '::-:'555g0i3000g0.:6 IF EQUALP:O: 3 THEN IGNORE PUTSNAP8 IF EQUALP :0:4 THEN IGNORE PUTSNAP10 IF EQUALP ;0; 5 THEN IG.~ORE PUTSNAP "9 3" --150 300·12 IF EQUALP :0: 6 THEN IGNORE PUTSNAP "10 3· "-150 300·14 IF EQUALP :0: 7 THEN IGNORE PU'l'SNAP ·,1 3- ·-150 300~

16 IF EOUALP :0: 8 THEN IGl.KIRE PUTSNAP :,'23

33: :-_"550° 330000.:

18 IF EQUALP :0; 9 THEN IGNORE PUTSNAP .

~~ i; ~gg:~ :g: ~g :: ~ii;S~~SEND

TO MOVE :z;10 IF MP ;Zz -\ ...~ THEN PAODLEMOVE "'Y1- THING ;Z: ELSE IF MP ;Z: -A O-THEN

PADDLEMOV,E "Y2· THING ;Z:END

TO WALLHI'l'10 IF EITHER LES5P :Y; ( - 350 ) GREATERP ;Y; 350 THEN-REFLECT -DYEND

TO PADDLEHIT1 TEST GREATERP IX: 05 IFTRUE IF BOTH LESSP ;Y; SUH :Y1: 70 GREATERP ;Y; ~Y1: 'l'HELIi REELECT -DX·10 IFFALSE IF Bora LESSP ;Y; SUM ;Y2; 70 GREATER? :Y; :Y2; THEN REFLECT

"DX·15 TEST GREATERP ;X: 35017 IFTRUE MAKE- -52" SUM :52:18 IFTRUE WIPE19 IFFALSE IF LES5P ;X; ( - 350 ) THEN MAKE ·51" SUM_;S1: 120 IFFALSE IF LESSP IX: ( - 350 ) THEN WIPE21 IF EITHER LESSP ;X; ( - 350 ) GREATERP :X; 350 THEN STARTEND

TO MP :R; :E:5 IF EMPTYP :E; THEN RETURN -FALSE·10 IF IS :R; FIRST ;E; THEN RETURN "'TRUE- ELSE -RETURN ttP :R: I1UTFIRST;E;END

TO PADDLEMOVE ;WHICH: :HOWMUCH20 MAKE :WHICH; LAST MOVESNAP LAST ;WHICH; SENTENCE ;HOWHUC1U 90END

TO REFLECT :P:10 MAKE :P: DIFFERENCE 0 THING :P:END

TO CLAP IX;10 SAY "APPLAUSE',,-15 IF EQUALP :X, 1 THEN DONE ELSE CLAP DIFFERENCE ;X: 1END

'I'O CHOOSE :Dex;; :CAT:5 TEST EQUALP R~~ 1 2 110 IFTRUE RsrURN PRODUCT ;DOG: :CAT;11 IFFALSE RE'rURN QUOTIENT ;DCX;: ; CAT:END

EXPERIMENTS IN TEACHING CHILDREN COMPUTER

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