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Transcript of Assess Reasoning
Assessing Reasoning 1
Assessing Mathematical Reasoning:
An Action Research Project
Jill Thompson
Michigan State University – TE 855
December 2, 2006
Assessing Reasoning 2
Introduction
To fully participate in 21st century society, it will be necessary for our students to possess the
ability to “analyze, reason and communicate effectively as they pose, solve and interpret
mathematical problems in a variety of situations…” (OECD, 2004, p. 37). Yet, traditional and
large-scale tests historically have not measured the full range of important mathematics.
According to Achieve Inc., the most challenging standards and objectives are the ones that are
either underrepresented or left out, and those that call for high-level reasoning are often omitted
in favor of much simpler cognitive processes (Rothman, Slattery, Vranek & Resnick, 2002, p. 8).
This is an important observation, because it has long been recognized that what is tested has a
significant influence on what is taught (NCTM, 1991, p. 9). Even if large-scale tests can evolve
to the point where they effectively assess important high-level standards, they constitute only one
piece of the assessment puzzle. A balanced approach to assessment is needed so that, in addition
to serving accountability purposes, the assessments also can influence instructional decisions.
Assessment for this purpose must be done frequently, and must consist of items designed to
measure both content and cognitive processes (NCTM, 1991, p. 9). Perhaps one of the most
important of the process standards is reasoning, since “mathematical reasoning is as fundamental
to knowing and using mathematics as comprehension of text is to reading”
(Ball & Bass, 2003, p. 29).
Assessing Reasoning 3
Focus
Because reasoning is such a critical cognitive skill, it is important for teachers to know how to
measure it. Teachers regularly use a variety of assessment practices in their classrooms,
including observations, discussion, performance tasks, and more traditional assessments such as
multiple-choice or short answer tests. Because formal assessment plays such an important role in
assigning course grades or evaluating the effectiveness of instruction both within the classroom
and increasingly within school districts, the purpose of this study is to seek an answer to this
question: what can formal assessment tasks tell us about students’ mathematical reasoning?
Review of Literature
In order to measure reasoning, it is first necessary to define it. There is not universal agreement
on its definition. Research clearly points out the role of formal proof and argument as a central
aspect of mathematical reasoning. This is consistent with Thompson’s (1996) description of
reasoning as “purposeful inference, deduction, induction and association in the areas of quantity
and structure” (Yackel & Hanna, 2003, p. 228). NCTM includes a reasoning and proof standard
that emphasizes formal argumentation processes, but also includes the process of making and
investigating mathematical conjectures and supporting conclusions with mathematically sound
arguments (2000, p. 342). The National Research Council describes mathematical reasoning as
“the ability to think logically about the relationships among concepts and situations”
(CFE, 2001, p. 129). Finally, researchers such as Lampert (2001) take a more social view of
reasoning as an important and public process arising from the interaction of learners as they
solve problems together.
Assessing Reasoning 4
In addition to providing insight into what constitutes mathematical reasoning, research can also
guide the design of assessment tasks. The Harvard Research Group Balanced Assessment Project
developed a program of assessment that consisted of tasks that would provide learning
opportunities for students while also serving as a basis for accountability measures. These tasks
were field tested, and fall into one of three categories. “Performance tasks” are short answer
constructed response items that measure students’ proficiency using skills and procedures.
“Problems” require extended responses, and provide information about a student’s ability to
model, infer and generalize. “Projects” can take from 20 minutes to an entire class period, and
provide information about a student’s ability to analyze, organize and model complexity
(Balanced Assessment, 1995, p. 18). An extensive scoring rubric was designed to assure validity
and reliability due to the complexity of the learning tasks.
Some of the most interesting research related to task design revolves around the use of a
framework for evaluating mathematical tasks based on the level of cognitive demand required by
the task. This framework was developed as part of a project intended to help teachers match
mathematical tasks to learning goals (Arbaugh & Brown, 2005, p. 506). Tasks were rated
according to the Level of Cognitive Demand (LCD) criteria at four levels. The two lowest levels
are memorization and using procedures without connections to meaning. Tasks at these levels
require recall and repetition of previously learned facts or routines, are generally unambiguous,
have no connections to concepts, and require explanations that focus only on the procedure that
was used to solve a problem. The two higher levels of cognitive demand involve using
procedures with connections to meaning or actually doing mathematics. Tasks at this level
require use of procedures that are closely connected to underlying concepts, may involve
Assessing Reasoning 5
multiple representations or pathways to a solution, require cognitive effort, and require complex
and non-algorithmic thinking (Arbaugh & Brown, 2005, p. 530). The results of the QUASAR
study that used this framework showed that when teachers choose and implement learning tasks
at the higher levels of cognitive demand, students show an increased level of understanding and
reasoning (Arbaugh & Brown, 2005, p. 527).
Research Questions
Following a review of the literature, the research question was narrowed to focus on the actual
assessment task design. This study seeks to answer the following questions:
1. What can formal assessment tasks tell us about students’ mathematical reasoning?
2. What can be learned about reasoning from multiple-choice versus constructed responses
questions?
3. What can be learned about reasoning from tasks at various levels of cognitive demand?
Mode of Inquiry
The mode of inquiry employed in this project can best be described as authentic practitioner
research within the grounded theory tradition. The intent of the project is to explore the
effectiveness of different types of learning tasks, both traditional and authentic, at varying levels
of cognitive demand. It is a grounded theory study because it involves detailed analysis of data
from more than one perspective, and its ideal outcome would be a theory which may or may not
need to be explored further using more empirical evidence (Creswell, 1998, p. 58).
Assessing Reasoning 6
Context
This study was conducted in one classroom and involved 60 students in two sections of
Algebra 2. Normal classroom practice includes both formal and informal assessment at frequent
intervals. The formal assessments typically consist of a mixture of short constructed response
items (the majority) and some multiple-choice items. The questions are developed by the teacher
and are loosely based on test items provided in the supplemental materials to the course
textbook. Tests always include one or two items that present an entirely new context within
which students are asked to apply the knowledge they have gained during the unit of instruction.
Typical classroom instruction involves daily opportunities for students to discuss their work,
primarily with each other in small group interactions. At least one class period each week begins
with opportunities for students to relate their recently acquired knowledge to other ideas and
prior knowledge. These activities are generally “warm-up” activities and precede direct
instruction. During whole class discussions, students are frequently asked to explain and justify
their conclusions or solutions. This style of discourse can encourage mathematical reasoning
because it creates an environment where it is important for students to communicate, explain,
justify, and form relationships between ideas (Yackel & Hanna, 2003, p. 229). However, it is
important to note that the curriculum materials are traditional and emphasize the development of
procedural knowledge.
Innovation
The innovation selected for this inquiry involved designing and implementing a set of learning
tasks that included standardized test questions drawn from different sources. The tasks were
deliberately selected at different levels of cognitive demand, based on the LCD criteria (Arbaugh
Assessing Reasoning 7
& Brown, 2005, p. 530). For purposes of this study, the tasks were classified at either the lower
level (memorization or procedures without connections to meaning) or the higher level
(procedures with connections or doing mathematics). They consisted of a mixture of constructed
response and multiple-choice items.
Two of the multiple-choice items were drawn from the Virginia End of Course Exam for
Algebra 2 (VDOE, 2000, p. 15). The third was an extended response item from the NAEP
(IES, 2006, p. E-33) and was rated at the moderate level of complexity for that examination,
which corresponds to the higher level of cognitive demand using the LCD criteria.
Three of the constructed response items were created with the intent of assessing students’
ability to reason through deduction, inference, and association (Yackel & Hanna, 2003, p. 228).
The remaining constructed response item was drawn from the course text. It required students to
compute and compare two quantities, and select the appropriate multiple-choice response based
on the comparison. Although the text presented the problem as a multiple-choice “test
preparation” item (Glencoe, 1998, p. 251), for purposes of this exercise, students were also asked
to show and explain how they approached the problem. A summary of the types of questions is
shown below, and the tasks and reasons for their classifications are shown in Appendix A.
Tasks by Format and Level of Cognitive Demand
Multiple Choice
Constructed Response
Lower level of cognitive demand Problems 1 and 2 Problem 5Higher level of cognitive demand Problem 7 Problems 3,4 and 6
Assessing Reasoning 8
A simple rubric was used to evaluate student responses to the constructed response items. It
involved a system of assigning up to four points:
SCORE CRITERIA
4 Response is substantially correct and complete
3 Response includes one significant error or omission
2 Response is partially correct with more than one significant error or omission
1 Response is largely incomplete but includes at least one correct argument
0 Response is based on incorrect process or argument, or no is response given
The assessment items, which all covered content related to the ongoing study of matrix
algebra, provided an opportunity for students to demonstrate their reasoning ability. Students are
best able to demonstrate reasoning ability when they possess a sufficient knowledge base, the
tasks are motivating, and the context is familiar (CFE, 2001, p. 129). This assignment was made
at the end of the unit of instruction, the format of the assignment was similar to previous class
projects, and the students were motivated both by the novelty of the tasks as well as the
communicated purpose of reviewing for their test. The students were given one class period to
complete the tasks, although some did not finish and required additional time outside the
classroom.
Data
The data used for this study included the responses of 48 students who completed the seven
learning tasks, and also their scores on the summative assessment for the unit. The data were
analyzed from three perspectives. First, the responses on the learning tasks were analyzed as to
evidence and quality of mathematical reasoning. Second, a comparison was made between
Assessing Reasoning 9
student performance on the learning tasks and their performance on the unit test using a simple
linear correlation. Third, student responses were reviewed for the existence of common themes.
A few problems emerged in the process of assigning the tasks and collecting the data. One of
these resulted from the fact that not all students were present or handed in the learning tasks on
the day they were assigned, so only 48 of the 60 students in the two Algebra 2 classes are
represented in the study. Some of the students requested additional time to complete the
assignment at home because they were concerned about the grade they would earn on the
assignment. Their responses (handed in the next day) were not included in the analysis because
the students were given additional time and resources to complete the project.
Also, while the project was intended to be an individual project, many students requested
clarification, either from the teacher or from each other, on two of the constructed response
items. Ultimately, students discussed and collaborated on the most difficult item, which asked
them to determine and justify their conclusion as to whether the commutative properties of
addition and multiplication apply to matrix addition and multiplication. Thus, student responses
on the learning tasks do not necessarily represent their own interpretation and approach.
Further, it was difficult to ascertain whether the papers that did not include responses to the last
few questions were unfinished, or whether students did not know how to approach the problems.
The non-response rate to the last few problems of the assignment may reflect a lack of time
rather than a lack of understanding.
Finally, during the analysis process, it became evident that the rubric designed to evaluate
student performance did not anticipate the wide variation seen in the students’ responses. To
adjust for this problem, the student responses were analyzed in two different ways. The rubric
Assessing Reasoning 10
was used only to assign a score for purposes of comparing student performance with their
performance on the summative unit assessment. Other analysis focused primarily on the
characteristics of the student responses, which were unique to each task.
Findings
The percentages of students who earned full credit for their responses on the various
assessment items was as follows:
Percentage of Students with Correct Responses or Rating of 4 on the Rubric
Level of Cognitive Demand
Multiple Choice
Constructed Response
Lower 96%, 98% 73%Higher 25% 0%, 60%, 83%
A discussion of students’ performance on each group of items follows, based on the format and
the level of cognitive demand required by the tasks.
Questions at Lower Level of Cognitive Demand – Multiple-Choice
As might be expected near the end of a unit instruction, there was a high rate of success on the
lower demand, multiple-choice items (problems 1 and 2). These are, coincidentally, both
standardized test items. These items were related to solving a linear system in three variables or
finding the inverse of a 2x2 matrix and required application of learned procedures.
Questions at Lower Level of Cognitive Demand - Constructed Response
The constructed response item at the lower level of cognitive demand (problem 5) required
students to identify whether a hypothetical student, “Ken”, correctly multiplied a 2x2
determinant by a constant, and to justify their conclusion. The success rate on this problem was
Assessing Reasoning 11
fairly high, although not as high as on the multiple-choice items. Despite the fact that 73% of the
students responded correctly on this item, only 58% of the students offered an explanation. Many
students thought it was adequate to show work as the explanation. Others provided more detail as
to the source of the error in Ken’s work, as in the response below:
The students who responded incorrectly repeated the error and arrived at an answer of “80”.
Applying the order of operations to determinants was a frequent topic of discussion during the
unit, yet almost 23% of the students still repeated the mistake.
Questions at Higher Level of Cognitive Demand - Multiple-choice
Problem 7 was originally designed to be a multiple-choice question and is reproduced below:
Assessing Reasoning 12
Although this problem was taken from the student textbook and was designated as standardized
test practice, it is clear that the design of the problem is flawed. It is possible for students to
incorrectly use “1” as the solution for Quantity A, or else make a calculation error, and still
arrive at the correct answer. In fact, while 25% of the students gave the correct response “A”,
almost half of them did so, either because they assumed the determinant value of “1” was also
equal to the value of the unknown, or else they used an incorrect formula to arrive at a number
that was still larger than y = -6. Further, the students who did not complete the determinant part
of the problem (23%) and the students who stated there was not enough information by choosing
answer D (6%) actually may have demonstrated a greater level of understanding than some of
the students who accidentally chose the correct answer, because they recognized the placement
of the unknown quantity inside the determinant as something requiring a novel approach. Using
this problem as a constructed response item provided much more insight into student
understanding than simply looking at the percentage who responded correctly.
Questions at Higher Level of Cognitive Demand - Constructed Response
The constructed response items at the higher level of cognitive demand showed widely variable
success rates, from 0% to 83%. Not surprisingly, these problems also provided the most insight
into students’ thought processes.
Problem 3 actually consisted of two parts: the first was the solution of a 3x3 system (similar to
question 1), and the second was an explanation of how students could tell their solution was
correct. While 83% of the students accurately determined that the system had no solution, only
69% of the students stated this explicitly. The other 14% of the students stated that the
determinant was equal to zero rather than stating that the system had no solution. Because
Assessing Reasoning 13
students had often encountered 2x2 systems in class (solved without graphing calculator
technology), they usually checked the value of the determinant first before trying to find the
inverse of the coefficient matrix.
Evaluation of students’ explanations of the results raises some interesting observations about
their understanding. Of those who presented a reasonable argument, a majority (60%) of the
students identified either that the value of the determinant was zero, or that the 3rd row of the
matrix was a multiple of the 1st row. Only one student presented both of these reasons,
recognizing that one caused the other. None of the students compared the result to the concept of
parallel lines in space, which had been a topic of discussion in a previous class session.
The remaining students presented no explanation (6%), had an incorrect response to the initial
problem (8%), or relied either on repetition or the calculator’s result of “Singular Matrix” as their
explanation (23%). This was probably the most informative of any of the learning tasks about
students’ perceptions about what it means to justify a conclusion or solution to a problem. The
results also raise the possibility that students are relying heavily on learned procedures, such as
using the calculator or finding the value of the determinant before attempting the multiplication
(as was done frequently in class when solving 2x2 systems without the calculator), to solve this
type of problem.
In examining students’ work on the NAEP application test item, it was interesting to note that
only 50% of the students used matrix algebra. The other 10% who were successful on this
problem reverted to strategies such as algebraic substitution or “guess and check”. This problem
actually provides more information about students’ problem-solving approach than it does about
Assessing Reasoning 14
their mathematical reasoning, but is representative of the typical items included on exams used to
compare the performance of US students to international standards.
The most interesting question to analyze was question 6, where none of the students responded
in a completely satisfactory manner. This question asked students to analyze matrix addition and
multiplication to determine whether the commutative property might apply:
The example shown above represents a partially correct response, but is significant because of
the attempt at generalization. Only two students arrived at a general argument about
multiplication using the dimensions of the matrices. While this response shows a high level of
reasoning in the connection between the matrix multiplication algorithm and the commutative
property, the response does not indicate whether the two students thought of a formal reasoning
process involving a counterexample, which was the approach selected by 27% of the students.
Given that it is more difficult to offer proof that a statement is true, it is not surprising that
none of the students were successful in providing a reasonable argument about addition. Only
15% of the students even attempted to address addition, and most did so using a specific
Assessing Reasoning 15
example, as shown in the response below:
It is important to note that, while students had previous experience with algebraic proofs in this
class, they had not been asked to prove general arguments about quantities. Therefore, this task
was completely novel, and drew primarily on the prior knowledge and reasoning capacity of the
students rather than the accumulated effect of recent instruction. Some of the incorrect responses
contained some very interesting connections, as in the cases where students tried to extend real
number properties to matrices because matrices are composed of real numbers. Expanding on
this reasoning could ultimately have led to a valid and defensible argument, and these students
demonstrated a novel approach and sophisticated connection between ideas that was not evident
in the responses of students who followed a more conventional path. It was on this problem that
the scoring rubric was the least helpful in making a quantitative assessment of student reasoning.
Not only was this task informative about reasoning, it is also possible to make evaluations of
students’ procedural knowledge. In the example, close examination reveals that the student has
problems arriving at the 2nd row 2nd column element each time she multiplies, possibly indicating
Assessing Reasoning 16
a problem with the matrix multiplication algorithm itself. Every student’s response provided a
wealth of information that would not have been evident in tasks at lower levels of cognitive
demand or multiple-choice format.
Themes
Adaptive reasoning includes students’ capacity for logical thought, explanation and
justification (CFE, 2001, p. 129) and the ability to use accumulated knowledge to solve new and
diverse problems (Ball & Bass, 2003, p. 28). In examining student work for evidence of
reasoning ability, a number of common themes and assumptions emerged that indicate problems
with mathematical reasoning. These were identified in the responses to item 3 (the explanation)
and item 6. They were:
Some students believe that showing work is sufficient explanation;
Some students believe that obtaining the same result through repetition is adequate
assurance that the conclusion or result is correct; and
Some students believe that giving one example provides a basis for generalizing that
something is always true.
A Comparison of Performances
To determine whether the data about student performance on the reasoning tasks was
consistent with student performance on the summative assessment, a simple linear correlation
was completed. Student performance on the unit assessment was very high, with a number of
students earning scores of 100% or more (due to inclusion of an extra credit question). However,
close examination of the summative assessment revealed that all but two of the questions on the
Assessing Reasoning 17
test could be rated at the lower levels of cognitive demand. Results of the correlation show an r2
value of 29%, indicating that 29% of the variation in the summative assessment score could be
explained by student performance on the learning tasks. When test scores of 100% or more were
excluded, the r2 value rose to 39%.
Other variables causing the relatively low r2 values could include variations in the approach to
scoring the tasks or a mismatch between the types of questions included in the learning tasks as
opposed to those on the summative assessment. However it is interesting to note that only four of
the 48 students earned a high score (above the median) on the assessment tasks and a low score
(below the median) on the summative assessment. A plot of the data is shown below.
Test Scores Related to Practice Sheet Scores
0
20
40
60
80
100
120
0 5 10 15 20
Practice Sheet Scores
Per
cen
tag
e o
n T
est
Assessing Reasoning 18
Conclusions and Implications
The findings clearly indicate that the constructed response items were the most valuable in
providing information about student reasoning. Also, the performance tasks designed at the
higher levels of cognitive demand generated the most variation in student responses and thus the
most insight into their thinking. Therefore, it is evident that designing constructed response items
at the highest levels of cognitive demand provide the best measures of student reasoning, despite
the inherent difficulties in scoring these items.
The scoring problem highlights a perplexing problem that has been facing the educational
community for some time. Assigning scores for assessment purposes becomes more difficult as
the complexity of assessment items increases, and it is inevitable that subjectivity in scoring will
enter the process, decreasing the reliability of the assessment. According to NCTM, assessment
should “promote valid inferences about mathematics learning”, and one threat to this validity is
the introduction of bias into the scoring process (1995, p. 19). Based on this problem, it is
possible to argue that classroom assessments should serve as the primary means of evaluating
students’ mathematical reasoning. The difficulty lies in defining what role this evaluation can
play in the current high-stakes testing environment and its reliance on standardized tests.
A surprising result of this study highlights the importance of using assessment to evaluate and
modify instructional practice. It was clear from the results of this study that the understanding of
many students could be described as procedural. If students are instructed with a focus on
mathematics as procedure, they are likely to rely on procedure in attempting to explain their
approach to a task, as evidenced by common themes identified in the student work. It is clear that
instruction must be modified to help students develop a view of mathematics as reasoning rather
Assessing Reasoning 19
than procedure. To this end, problems such as the one dealing with the commutative property
present a unique opportunity if they are used to help develop reasoning in the classroom
community as a whole. All of the elements of a sound mathematical argument were present in
the students’ responses, yet students had no opportunity to share them with each other.
Vygotsky’s theory of social constructivism suggests that learning occurs when one shares ideas
with more capable peers, lending support to the idea that group tasks are useful in helping
students develop understanding (NCRMSE, 1991, p. 12) and therefore reasoning.
To return to the one issue that may have the most alarming implications, the difficulty in
scoring the complex assessment items raises questions about whether standardized test items will
ever be able to adequately measure reasoning. NCTM’S coherence standard argues for a
balanced approach to assessment where the various types and phases of assessment are matched
to their purpose (1995, p. 21). In order to measure the important standard of mathematical
reasoning, students must be provided with instruction that allows them to invent, test and support
their own ideas, and assessment items must measure whether students are able to apply their
knowledge in novel situations (Battista, 1999, p. 15). Yet, with the unprecedented pressure of the
accountability movement and massive revisions to state curriculum standards, there is evidence
that instruction is increasingly focused on test preparation and that the quality of instruction is
actually decreasing (Popham, 2004, p. 31). One can only hope that future studies confirm the
value of focusing instruction on important standards such as reasoning, and that doing this will
naturally lead to better performance on standardized tests.
Assessing Reasoning 20
Bibliography
Arbaugh, F. & Brown, C.A. (2005). Analyzing mathematical tasks: A catalyst for change?
Journal of Mathematics Teacher Education 8(499-536).
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and Skills Effectively: An Interim Report of the Harvard Group.
Retrieved online 10/2006 from http://balancedassessment.concord.org/amuse.html
Ball, D.L. & Bass, H. (2003). Making mathematics reasonable in school. A Research Companion
to Principles and Standards for School Mathematics, (27-44). Reston, VA: NCTM
Battista, M. (1999). The miseducation of America’s youth. Phi Delta Kappan Online.
Retrieved 10/28/2006 from http://.www.pdkintl.org/kappan/kbat9902.htm
Center for Education of the National Research Council (CFE), (2001). The strands of
mathematical proficiency. Adding it up: Helping children learn mathematics (115-156).
Retrieved online 9/2006 from http://www.nap.edu/books/0309069955/html
Creswell, J.W. (1998). Qualitative inquiry and research design: Choosing among five traditions.
Thousand Oaks, CA: Sage Publications.
Glencoe (1998). Algebra 2.Columbus, OH: McGraw-Hill
Institute of Educational Sciences (IES), (2006). Comparing mathematical content in the NAEP,
TIMSS and PISA 2003 assessments: Technical report. USDOE: National Center for
Education Statistics, Institute of Education Sciences, NCES 2006-029
Lampert, M. (2001). Teaching problems and the problems of teaching. Newhaven, CT: Yale
University Press
Assessing Reasoning 21
National Council of Teachers of Mathematics (NCTM), (1991). Assessment: Myths, models,
good questions and practical suggestions. Reston, VA: NCTM
National Council of Teachers of Mathematics (NCTM), (2000). Principles and standards for
school mathematics. Reston, VA: NCTM.
National Center for Research in Mathematical Sciences Education (NCRMSE), (1991). A
framework for authentic assessment in mathematics. NCRMSE Research Review,1(1).
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tomorrow: First results from PISA 2003. Retrieved online 10/16/2006 from
http://www.pisa.oecd.org/dataoecd/1/60/34002216.pdf
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30-33. Reprinted with permission online, retrieved 10/28/2006 from ASCD.org.
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standards and testing: CSE technical report 566. Retrieved online 12/1/2006 from
http://achieve.org/files/TR566.pdf
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course examination. Retrieved online 11/1/2006 from
http://www.pen.k12.va.us/VDOE/Assessment/release2000.algebra2.pdf
Yackel, E. & Hanna, G. (2003). Reasoning and proof. A Research Companion
to Principles and Standards for School Mathematics,(227-249). Reston, VA: NCTM
Assessing Reasoning 22
Appendices
Appendix A: Learning Tasks, Source, and Reason for Ratings Using LCD Criteria.
Task 1: Solve a 3x3 linear system with a missing variable Format: multiple-choice Source: Virginia End of Course Exam for Algebra 2: Released Items (VDOE, 2000) Level of Cognitive Demand: Lower (Procedures without connections to meaning),
because students are required to execute a procedure evident from prior instruction in order to solve for the missing variable.
Task 2: Find the inverse of a 2x2 matrix with a determinant not equal to 1 Format: multiple-choice Source: Virginia End of Course Exam for Algebra 2: Released Items (VDOE, 2000) Level of Cognitive Demand: Lower (Procedures without connections to meaning),
because students need to execute a procedure evident from prior instruction in order to find the inverse of the matrix.
Task 3: Solve a 3x3 linear system given in standard equation form, with a result of “no solution”, and explain the results
Format: constructed response Source: teacher Level of Cognitive Demand: Higher (Procedures with connections to meaning), because
students need to engage with underlying concepts to explain why the system has no solution, and they need to make connections within mathematics to interpret the results.
Task 4: Solve a problem with two variables and two constraints set in a real-life context Format: extended constructed response Source: NAEP, Example 24 (IES, 2006, p. E32) Level of Cognitive Demand: moderate according to NAEP, corresponds to higher
(Procedures with connections to meaning), because students need to represent the constraints in symbolic form after interpreting from the real life context and then execute one of several possible procedures to arrive at a reasonable solution, which should consist of integers based on the context of the problem.
Assessing Reasoning 23
Appendix A (continued)
Task 5: Determine whether the example showing an incorrect calculation of the product of a scalar and a 2x2 determinant is correct, and then explain why the solution presented is wrong.
Format: constructed response Source: teacher Level of Cognitive Demand: Lower (procedures without connection to meaning) because
students need to know the order of operations, which was evident from prior instruction, and make a straightforward argument about what step was incorrectly applied in the illustrated solution.
Task 6: Justify application of the commutative properties of multiplication and addition to matrix operations.
Format: extended constructed response Source: teacher Level of Cognitive Demand: Higher (doing mathematics) because students were asked to
engage in complex and non-algorithmic thinking in an entirely new context. The task required exploration of mathematical contexts and application of connected ideas from different mathematical settings as well as a high level of anxiety, since a correct approach or solution was not evident.
Task 7: Calculate the value of an unknown in a 3x3 determinant given the value of the determinant, and compare this to the value of “y” in the solution of a 3x3 linear system to determine which quantity is the greatest.
Format: multiple-choice Source: Glencoe standardized test practice (Glencoe, 1998, p. 251) Level of Cognitive Demand: higher (procedures with connections to meaning) because
the task required a degree of cognitive effort due to the placement of the unknown value inside the 3x3 determinant. Although students could use previously learned procedures, they could not do so mindlessly. Additional complexity was introduced by requiring the comparison of two quantities to select the correct multiple-choice response.
Assessing Reasoning 24
Appendix B: Detailed Evaluation of Student Responses on Performance Tasks
Item 1: Solve 3x3 systemStudent Responses # % of Total
Correct Response 46 95.8%
Incorrect Response 2 4.2%
Item 2: Find 2x2 InverseStudent Responses # % of Total
Correct Response 47 97.9%
Incorrect Response 1 2.1%
Item 3: Problem: 3x3 System with No SolutionStudent Responses # % of Total
Correct (No solution) 33 68.8%
Correct, but stated determinant = 0 7 14.6%
Incorrect response (found solution or A inverse) 4 8.3%
No response 4 8.3%
Item 3 Explanation of how students know if they are correctStudent Responses # % of Total
Correct; multiple reasons given 1 2.1%Correct; determinant = 0 20 41.7%Correct; 3rd row is multiple of 1st row 9 18.8%Incorrect or reliance on calculator or repetition 15 31.3%No response 3 6.3%
Item 4: NAEP Application Problem, 2 variables and 2 constraintsStudent Responses # % of Total
Correct response 29 60.4%Incorrect response; 2 correct constraints 9 18.8%Incorrect response; 1 correct constraint 5 10.4%No response 5 10.4%Of the correct responses, all but five students used matrices. Three used algebraic substitution and two used "guess and check". One student with an incorrect response set up the constraints as inequalities.
Item 5: Product of scalar and determinant, explanation of error in order of operationsStudent Responses # % of Total
Correct conclusion with explanation 28 58.3%Correct conclusion; no explanation, showed work 6 12.5%Correct conclusion; no supporting work 1 2.1%Incorrect conclusion 11 22.9%No attempt 2 4.2%
Assessing Reasoning 25
Appendix B (continued)
Item 6: Commutative property application to matrix multiplication and additionStudent Responses # % of Total
General reasoning for addition; counterexample for multiplication 0 0.0%Example for addition; counterexample for multiplication 7 14.6%No conclusion for addition; counterexample for multiplication 6 12.5%No conclusion for addition; used dimensions for multiplication 2 4.2%Example for addition; nothing for multiplication 6 12.5%Too general of a conclusion or incorrect reasoning 7 14.6%No attempt 20 41.7%
Two students concluded that since matrices are composed of real numbers, real number properties should apply to matrices. Five students used the identity matrix to show the commutative property of multiplication worked in that one instance and concluded that matrix multiplication is commutative. None of the thirteen students who argued that the commutative property of addition worked for addition were able to provide a general argument: they relied on a single example that worked. Some students concluded neither property worked because there are instances where it is impossible to add or multiply matrices because of their dimensions. Two students were able to present a general argument for matrix multiplication using dimensions of rectangular matrices and showing that the order of multiplication could not be reversed. Two students referenced the idea of a determinant, indicating they were thinking about inverses.
Item 7: Comparison of unknown element in determinant and one variable in 3x3 systemStudent Responses # % of Total
Correct response 7 14.6%Correct response; incorrect calculations or assumptions 5 10.4%Incorrect response: concluded "not enough information" 3 6.3%No response: problem partially attempted (3x3 system) 11 22.9%No response, no attempt evident 22 45.8%
Students making an incorrect assumption about the given information could actually have gotten the correct answer to this problem, while students who concluded "not enough information" probably had a better understanding of the problem.