November/December 2009 • DynaMath • T1

Teacher’s eDiTioN

Nov./Dec. 2009Vol. 28, No. 3

ISSN 0732-7773

A SupplemeNt to Dynamath

scholastic DynaMath557 Broadway, room 4052

New York, NY 10012(212) 343-6458

DynaMath@scholastic.com

sUBscriPTioN/DeLiVerY iNQUiries:

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DynaMath gives students lots of reasons to think about math this season! For example, November is Diabetes Awareness Month. Pages 10–11

show how Nick Jonas and other people with diabetes use math to track their insulin needs.

November also marks the start of the new NBA season. Students can see the amazing heights of various pro players on pages 4–5.

Finally, pages 8–9 and 12–13 put fun spins on the gift-giving season.

Wishing you math-y holidays,

Matt Friedman, Editor

’Tis the Season for Math

Content and SkillS GuideDifficulty Level: H = Easy HH = On-Level HHH = Challenging

PaGe arTicLe TiTLe,DiFFicULTY LeVeL

PriMarY MaTh sKiLL sUPPLeMeNTarYsKiLLs/aPPLicaTioNs

NcTM sTaNDarDs(see below for details)

cover Game Time HH Multistep problem Computation +, – 1, 6, 7, 8

2–3 Numbers in the News H H Mixed skills Word problems, pattern 1, 2, 6, 8, 9

4–5 Tall Ordering HH Median and mode Statistics, computation +, 5 1, 2, 5, 6, 7, 8, 9

6–7 Rescue Operation HH choosing an operation Vocabulary 1, 2, 6, 7, 8

8–9 Toy Store-y HH Money computation Running a business 1, 6, 9

10–11 Diabetes Doesn’t Stop . . . HHH Division Ratios 1, 4, 6, 9

12–13 A Gift for Geometry H identifying 3-D shapes Names of 3-D shapes 3, 8, 10

14–15 Dr. ART HH issue skills review Test-taking practice 1, 3, 4, 5, 6

16 Dwayne’s Multiples HH Multiples of a number Computation 5 1, 8

T4 Median Mode Music HH reading a line plot pp. 4–5 extension 1, 4, 5, 8, 9, 10

T5 Problem Solved Prep Page H context clue pp. 6–7 warm-up 1, 8

T6 Factor Fiction? H Factors p. 16 extension 1, 8

issue Dates: 9/09 10/09 11–12/09 1/10 2/10 3/10 4/10 5-6/10

Need Funding for DynaMath?Go to www.scholastic.com/classmags and click on Looking for Funding to learn how DynaMath qualifies for funding, such as NCLB grants.

NcTM standards 1. Number and Operations 2. Algebra 3. Geometry 4. Measurement 5. Data Analysis & Probability

6. Problem Solving 7. Reasoning and Proof 8. Communication 9. Connections 10. Representation

Standards listed above in a bold box (such as 1) indicate that the article also connects with a new NCTM Curriculum Focal Point.

Your STudenTS can win a dYnaMaTh T-ShirT!ask your students to be on the lookout for interesting events or places that they’d like DynaMath to feature in “Numbers in the News.” have them send a copy of, or a Web link to, their news idea. if we use it in the magazine, they’ll win a T-shirt. see page 3 of this issue’s student edition for details.

2-3: NUMBERS IN THE NEWS

STRATEGY: HIGH THERE

Remind students to use commas to

separate place-value periods when

writing numbers in standard form or

word form.

BONUS QUESTION: TRUNK . . .

About how many tons does Tarra

weigh? (Answer: about 4 tons)

EXTENSION: WACKY FACT

Have students write the answer in

word form and in number form.

4–5: TALL ORDERING

STRATEGY: DOUBLE-CHECK

Make sure students don’t skip any

numbers when writing the data in

order from least to greatest. Have

them count the number of numbers

in the original set of data and com-

pare that with the number of num-

bers in the ordered set. Or have them

cross out each number in the original

set of data as they write it in the list of

numbers from least to greatest.

EXTENSION: MEDIANS

Explain why the median (rather than

the mean) is often used to describe a

set of data. Use the following exam-

ple: A group of students ran a mile.

Their times in minutes were 10, 12,

9, and 10. The mean of these num-

bers is 10.25. This is a fair average

of the times. Now, add in the time

of an adult world-record holder at

4 minutes. The mean is now 9 min-

utes. This really doesn’t represent a

fair “average” of all of the runners.

However, the median of all 5 run-

ners is 10 minutes, which gives a fair

“average” of the times of the runners.

Medians are used to compare such

things as salaries and house prices,

which often have a very wide range

in the set of data, but where most of

the data fall in a cluster.

6–7: RESCUE OPERATION

STRATEGY: INTRODUCTION

Use the reproducible found on page

T4 to introduce the concept of using

context clues along with clue words

when determining the operations to

use in solving word problems.

EXTENSION: BONUS QUESTION

Based on the answer from problem

#5 (1,484 chairs), if 273 people are

in the school and they all sit in the

auditorium, how many chairs would

be empty? (Answer: 1,211 chairs)

8–9: TOY STORE-Y

VOCABULARY REVIEW:

Wholesale—The discounted price

at which a store buys a large number

of a product from the manufacturer.

Profit—The amount of money

remaining after an item is sold and

all expenses have been paid.

RESOURCE: WEB SITE GAME

Students can have fun and learn

about running their own lemon-

ade stand business at http://www

.classbrain.com/cb_games/cb

_gms_bag/lemonade.html . . . !

STRATEGY: BACKGROUND

Point out to students that diabe-

tes cannot be “caught” like a cold.

Diabetes occurs when the body’s

immune system turns against the

insulin-producing cells of the pan-

creas. The cause of this occurrence is

not fully understood.

EXTENSION: WEB SITE

Students can learn about how dia-

betes is controlled by taking care of

a computer dog that has the disease:

http://nobelprize.org/educational

_games/medicine/insulin/game

/insulin.html

14–15: DR. ART

EXTENSION: REWRITE PROBLEM

Have students rewrite three of the

article’s multiple-choice problems so

that, for each one, one of the original

incorrect answers becomes the new

correct answer.

16: DWAYNE’S MULTIPLES

VOCABULARY REVIEW:

Multiple—Any number in the series

of products of an integer and a spe-

cific given number. Multiples can be

identified by dividing a number by

the given number. If the result is an

integer, the number is a multiple of

the given number.

—Dale Beltzner

Mr. Beltzner is the Math Subject

Area Leader for the Southern Lehigh

School District in Bethlehem, Pa.

Lesson plans

T2 • DynaMath • November/December 2009

TEACHERS: Make one copy per student, or assign one problem each day to start your math lesson!

November/December 2009 • DynaMath • T3

Prob

lem

of

the

Day

Try

one

of t

hese

qui

ck e

xerc

ises

eac

h da

y as

a f

ast,

fun

way

to

star

t yo

ur m

ath

less

on!

Nam

e __

____

____

____

____

____

____

____

____

____

Problem of the Day by Dale Beltzner. Scholastic Inc. grants teachers permission to reproduce this page. ©2009 by Scholastic. All rights reserved.

DA

Y 1

W

hat

four

-dig

it

num

ber

am

I?

3

The

sum

of

my

dig

its

is 4

.

3 T

he p

roduc

t of

my

dig

its

is 1

.

DA

Y 6

W

hat

is t

he m

issi

ng

dig

it?

5

6 7

8 9

__

0 1

1 1

2

DA

Y 1

1 I

have

6 c

oins

. The

su

m o

f th

eir

valu

es is

10 c

ents

. W

hat

coin

s do

I ha

ve?

DA

Y 1

6

Uns

cram

ble

thes

e le

tter

s to

spe

ll th

e w

ord

form

s of

tw

o nu

mbe

rs:

W O

L N

T E

E E

V

(Hin

t: B

oth

num

ber

s ar

e le

ss t

han

20

.)

DA

Y 2

S

witch

tw

o dig

its

in

this

box

so

that

eve

ry

colu

mn,

row

,

and d

iago

nal

has

a su

m

of 1

5.

DA

Y 7

B

J ha

d 10

bea

ns a

t br

eakf

ast, t

wic

e as

man

y at

lun

ch, an

d 10

mor

e at

din

ner

than

at

lunc

h.

How

man

y be

ans

did

he

eat

alto

geth

er?

DA

Y 1

2

A 1

0-y

ear-

old b

oy’s

he

art

bea

ts 9

5 ti

mes

ea

ch m

inut

e. H

ow m

any

tim

es d

oes

the

boy

’s

hear

t bea

t in

one

day

(2

4 h

ours

)?

DA

Y 1

7

A p

aper

clip

is

mad

e fr

om 4

inc

hes

of w

ire.

H

ow m

any

paper

clip

s ca

n be

mad

e fr

om

1 ya

rd o

f w

ire?

DA

Y 3

W

hat

is t

he m

issi

ng

num

ber

?

50

= _

_ –

11

DA

Y 8

W

rite

the

nex

t tw

o nu

mber

s th

at c

onti

nue

this

pat

tern

:

12, 2

1, 1

3, 3

1, 1

4, _

_, _

_

Da

y 1

8

Use

onl

y th

e dig

it

9 m

ulti

ple

tim

es t

o co

mple

te t

his

equa

tion

: __

___

÷ _

____

= 1

1

DA

Y 4

If

3 r

abbit

s ca

n ea

t

12 c

arro

ts in

1 ho

ur,

how

man

y ca

rrot

s

can

6 r

abbits

eat

in

a ha

lf h

our?

DA

Y 9

W

hat

is t

he s

um o

f th

e nu

mber

s 1

thro

ugh

9?

Find

the

sum

usi

ng

only

men

tal m

ath

and

com

pati

ble

num

ber

s.

DA

Y 1

4

If a

= 1

, b

=2, c

= 3

, an

d s

o on

, w

hat

is t

he

sum

of

the

lett

ers

in t

he

wor

d “

succ

ess”

?

DA

Y 1

9

Out

of

16 a

liens

, so

me

had

2 ar

ms.

The

res

t ha

d 4 a

rms.

In

all,

ther

e w

ere

44 a

rms.

How

m

any

alie

ns h

ad 2

arm

s an

d ho

w m

any

had

4?

DA

Y 5

W

hat

do

all of

the

fo

llow

ing

num

ber

s ha

ve in

com

mon

?

37

19

46

55

DA

Y 1

0

If 1

gal

lon

of p

aint

co

vers

20

0 s

qua

re

feet

, ho

w m

uch

pain

t is

nee

ded

to

cove

r 50

0 s

qua

re f

eet?

DA

Y 1

5

A t

oy’s

cos

t w

as $

24.

Sto

re A

is

offe

ring

$10

of

f th

e fu

ll pr

ice.

Sto

re

B is

offe

ring

hal

f of

f th

e fu

ll pr

ice.

Whi

ch

has

the

bett

er d

eal?

DA

Y 2

0

Use

the

num

ber

s in

th

e to

p r

ow t

o find

th

e m

issi

ng d

igit

in

the

bot

tom

row

. 2

5

3

6

5

5

1

0

1 8

__

5

SK

ILL

S P

AG

E

DA

Y 1

3

Abou

t ho

w m

any

day

s w

ould

it

take

to

coun

t to

1,0

00,0

00

if

you

coun

ted 1

num

ber

ea

ch s

econ

d w

itho

ut

stop

pin

g?

61

8

45

3

29

7

Name______________________________________

Median Mode MusicThe members of the new band The Bogus Brothers (and Sister) are getting ready for their first concert. Kent Play will be keeping the beat on drums. Otto Tune is the lead singer. And Viola Linn tries her best on guitar. (She’s really much better with the violin.) How long does each member of the band practice each week? Read the line plots below to find out.

Kent Play’s Practice during 1 Week x x x x x x x0 1 2 3 4 5 61. What is the mode of Kent’s set above?

2. What is the median of Kent’s set above?

Otto Tune’s Practice during 1 Week

x x x x x x x0 1 2 3 4 5 6

3. What is the mode of Otto’s set above?

4. What is the median of Otto’s set above?

Viola Linn’s Practice during 2 Weeks

x x x x x x x x x x x x x x0 1 2 3 4 5 6

5. What is the mode of Viola’s set above?

6. What is the median of Viola’s set above?

Act

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Extension Activity

What to Do4 A line plot is a way of showing data on a graph. In the line plots below, each x represents one day of the week. Because there are 7 days in the week, there are 7 xs on this plot. 4 To find the mode, look for the number with the most xs. 4 To find the median, pick the middle number on the plot. Out of 7 numbers, the 4th number is the middle point. Starting at the left of the plot, count to the fourth piece of data: 4 hours is the median.

Example: practice during 1 Week x x x x x x x x0 1 2 3 4 5 6 (number of

hours per day)

(number of hours per day)

(number of hours per day)

(number of hours per day)

1

3

2 4

T4 • DynaMath • November/December 2009

Name______________________________________

Mathematical Context Clues Some clue words, such as “altogether,” can

be used in different ways. “Altogether” can be a clue either to add or to

multiply. So how do we decide which operation to use? Use other context clues found in the sentences of the problem. Example:

Maurice collected 15 football cards. A friend gave him 5 more football cards. How many football cards did Maurice have altogether?

3 Circle the number facts: 15 football cards, 5 football cards. 3 Circle other clue words: collected, gave.

Maurice collected 15 football cards. A friend gave him 5 more football cards. How many football cards did Maurice have altogether?

3 Make a decision to multiply or add.

3 In this problem, we should add: 15 cards + 5 cards = 20 football cards

Follow the directions to solve another problem.

Example: Maurice put his football cards in a book. Each page has room for 4 rows of cards with 5 cards in each row. How many cards does each page hold altogether?

3 Circle the number facts in the problem above: 4 rows, 5 cards. 3 Circle other clue words: with, in each row. 3 Make a decision to multiply or add.3 In this problem, we should multiply: 4 rows 5 5 cards = 20 cards

Extra Hints3 If the unit labels for the number facts are the same (like in the first problem, where “football cards” was the unit label), you will probably add or subtract. 3 If the labels are different (as in the second example, where “4 rows of cards” and “5 cards in each row” were the unit labels), you will probably multiply or divide. 3 The word “of” often means to multiply.

Now it’s your turn to be a detective. Track down clue words to solve a mystery in “Rescue Operation” on pages 6 and 7!

Act

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Warm-up activity

Problem Solved Prep Page

Context CluesOn pages 6 and 7, you’ll learn how to use clue words to figure out which operation you’ll need to

solve word problems. Here are some tips on spotting context clues that give extra help!

November/December 2009 • DynaMath • T5

Name______________________________________

T6 • DynaMath • November/December 2009

Factor Fiction?Find out which of our fun facts are true—and which we made up—by working with factors.

Factor Facts3 To see if one number is a factor of another, divide the second number by the first number. The first number is a factor if the quotient is a whole number, meaning there is no remainder.Example: Is 7 a factor of 17?3 17 ÷ 7 = 2 R33 The quotient has a remainder, so 7 is not a factor of 17.Example: Is 5 a factor of 15? 3 15 ÷ 5 = 33 Because the quotient (3) is a whole number with no remainder, 5 is a factor of 15.

1 In Sweden, people think that if a ladybug lands on a woman’s hand, 16

A {1, 2, 4, 8, 16} she will soon get married!B {1, 6, 8, 16} she will have 2 years of bad luck!

2When he was younger, President Barack Obama worked 21

A {3, 7, 21} as a paperboy. B {1, 3, 7, 21} at a Baskin-Robbins ice cream

shop.

3Before he was called Mickey Mouse, the cartoon character was named 30

A {1, 2, 5, 10, 15, 20, 30} Elvis. B {1, 2, 3, 5, 6, 10, 15, 30} Mortimer.

4Benjamin Franklin wanted the official bird of America to be 37

A {1, 37} the turkey. B {1, 3, 7, 9, 37} the duck.

5 The first TV commercial was an ad for 24

A {1, 2, 4, 9, 12, 24} canned spinach, in 1952. B {1, 2, 3, 4, 6, 8, 12, 24} watches, in 1941.

6The planet Uranus has more than 25 moons. Most are named for 60

A {1, 2, 3, 5, 6, 16, 26, 40, 60} Queens of England

B {1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60} characters in plays by famous writer William Shakespeare.

What to Do3 Each statement lists a number. 3 Find the set below that lists only the correct, full set of factors for that number. 3 Fill in the circle next to the correct set. 3 The phrase next to the correct set completes the true fun fact. The phrase next to the incorrect set is false.

Act

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Extension Activity