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Lesson 3�10 229

Advance PreparationTwo calculator programs are included in this lesson. Before you begin this lesson, decide which program you

should teach based on the calculators available at your school. You should only present one program.

Teacher’s Reference Manual, Grades 1–3 pp. 114, 115

Key Concepts and Skills• Count forward and backward by 1s, 2s,

and 5s from a given number.

[Number and Numeration Goal 1]

• Read numbers and symbols on a calculator.


• Use the +, -, and = symbols to count

forward and backward on a calculator.

[Patterns, Functions, and Algebra Goal 2]

Key ActivitiesChildren learn to count up and back using

a calculator.

Ongoing Assessment: Recognizing Student Achievement Use Mental Math and Reflexes. [Number and Numeration Goal 1]

Ongoing Assessment: Informing Instruction See page 232.

Key Vocabularyprogram

MaterialsHome Link 3�9

calculator � overhead nickels and pennies

(optional) � overhead calculator (optional)

Playing Penny-Nickel Exchangeper partnership: 20 pennies and

10 nickels, die (using a second die

is optional)

Children practice skip counting

with money.

Finding Sums of Three NumbersMath Masters, p. 305

per partnership: 3 dice

Children practice adding three 1-digit

numbers.

Math Boxes 3�10Math Journal 1, p. 45

Children practice and maintain skills

through Math Box problems.

Home Link 3�10Math Masters, p. 80

Children practice and maintain skills

through Home Link activities.

Minute Math +Minute Math ®+, pp. 10 and 46

Children practice addition and

subtraction concepts.

ENRICHMENTChecking Frames-and-Arrows Problems with a CalculatorMath Journal 1, p. 43

calculator

Children use their calculators to check

solutions to Frames-and-Arrows problems.

EXTRA PRACTICE

Skip Counting Math Masters, p. 68

Children practice skip counting by counting

up and back on number lines.

Teaching the Lesson Ongoing Learning & Practice

132

4

Differentiation Options

Counting witha Calculator

Objective To introduce counting up and back on the calculator.

��

eToolkitePresentations Interactive Teacher’s

Lesson Guide

Algorithms Practice

EM FactsWorkshop Game™

AssessmentManagement

Family Letters

CurriculumFocal Points

Common Core State Standards

229_EMCS_T_TLG1_G1_U03_L10_233812.indd 229229_EMCS_T_TLG1_G1_U03_L10_233812.indd 229 2/18/11 12:58 PM2/18/11 12:58 PM

230 Unit 3 Visual Patterns, Number Patterns, and Counting

1 Teaching the Lesson

� Counting Up and Back WHOLE-CLASS ACTIVITY

with a CalculatorTell children that they are going to learn how to use a calculator to count.

Review some of the basic rules for using calculators:

� Do not drop or throw calculators.

� It is easier to use a calculator when it is on a firm, flat surface.

� Press the middle of a key to make sure that only one key is pressed at a time. Discuss the various meanings of the word key and the meaning in this context.

� Use only your finger to press a key.

Write the following information on the board:

Getting Started

Home Link 3�9 Follow-Up Children share strategies for figuring out the missing rules.

Mental Math and Reflexes Do “stop-and-start” counts by 5s, and then by 1s. Count by 5s beginning with 0. Stop at 25. Then continue counting by 1s to 29.

Put a collection of pennies and nickels on the overhead (or draw them on the board). Count them in unison, first counting the nickels by 5s and then counting the pennies by 1s. Repeat as time allows.

NOTE Most basic four-function calculators

provide for counting up and back. Read the

instruction manual for the calculator that your

class is using for a description of the counting

(constant) function.

Start at: 0Count: upBy: 2s

Ongoing Assessment: Mental Math

and Reflexes�Recognizing Student Achievement

Use Mental Math and Reflexes to assess children’s ability to count by 5s

and then by 1s. Children are making adequate progress if they are able to

count on by 1s after they have stopped counting by 5s. Some children

will be able to make the counting transition more easily than others.


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Before you use the calculator to count, you must program it, or get it ready to count. Discuss the various meanings of the word program and the meaning in this context. Describe how to program the calculator to count up by 2s, as children follow along on their calculators. You may find it helpful to use an overhead calculator. Use the program that follows if your class is using the TI–108.

1. Press ON/C . This clears your calculator.

2. Press 0. This is the starting number.

3. Press the + key. This tells the calculator to count up.

4. Press 2. This tells the calculator to count by 2s.

Now the calculator is ready to start counting by 2s. Direct the class to do the following:

● Without clearing your calculator, press the

=

key. Which number is in the calculator display? 2

● Without clearing your calculator, press the

=

key again. Which number is in the display now? 4

● Continue to press the

=

key. (Each time, the class calls out the number in the display.)

Repeat the procedure, this time counting up by 5s, starting at 0. Write the following information on the board:

Have a volunteer describe how to program the calculator to count by 5s, as the class follows along.

Next, write the information for counting back by 1s, starting at 12, on the board:

Lesson 3�10 231

NOTE Some people find it helpful to use

the nonwriting hand for calculator keying

while keeping the writing hand available for

recording. In a playful, challenging way, see

if children can do the counts using their

nonwriting hands.

NOTE Different calculators may have

different programs for counting. If your class

is using the Casio SL-450L, use the program

that follows.

1. Press the key to clear the

calculator.

2. Press the count up number, in this

case 2.

3. Press to tell the calculator to

count up.

4. Press the start number, in this case 0.

5. Press the key to run the program.

You may enter a new starting number and the

key, and the calculator will continue to

count by 2s.

To count back, press .


Start at: 12Count: backBy: 1s



Adjusting the Activity


Describe what happens when you press the

=

key again after 0 has

been displayed. You get –1 Do this several times. What are these numbers

called? Negative numbers

A U D I T O R Y � K I N E S T H E T I C � T A C T I L E � V I S U A L

Describe how to program a calculator to count back. Use the

steps taught on page 231, but press – instead of + .

Ask: How is programming the calculator to count up different from

programming it to count back? To count up, press the + key;

to count back, press the –– key.

Do a few more counts back from a given number on the calculator.

� Counting Up, Starting WHOLE-CLASS ACTIVITY

from Any NumberAsk someone to supply the information for counting up by 2s, starting at 5. Write it on the board, as follows:

Give children a couple of minutes to program their calculators to

do this count. Children should press the

=

key a few times to check that they have programmed their calculators correctly. Have a volunteer describe what he or she did as the class follows along. Ask: How is programming the calculator to count up from 5 different from programming it to count up from 0? 5 is used as your start number rather than 0.

Do a few more counts up, starting with numbers other than 0.

Ongoing Assessment: Informing Instruction

Watch for children who do not clear their calculators before starting a new count.


Lesson 3�10 233

2. Make sums of 10 pennies.1. Odd or even?

Math Boxes LESSON

3 �10

Date

11109876543210

3. Use a calculator. Count up by 3s.

0, 3, 6,

, , ,

, , ,

,

Left Hand Right Hand

7 3

4

8

Answers vary.

62

4. What is the number model?

Fill in the circle next to the best answer.

A 3 + 5 = 7

B 4 + 3 = 7

C 3 - 4 = 7

D 3 + 4 = 7

even

even

odd

odd

91827

122130

1524

EM3MJ1_G1_028-053_Unit3.indd 45 1/17/11 6:40 PM

Math Journal 1, p. 45

Student Page

2 Ongoing Learning & Practice

� Playing Penny-Nickel Exchange PARTNER ACTIVITY

Children practice skip counting with money by playing Penny-Nickel Exchange. For detailed instructions, see Lesson 2-10.

� Finding Sums of Three Numbers PARTNER ACTIVITY

(Math Masters, p. 305)

Provide pairs of children with 3 dice. Children take turns rolling the dice, writing addition number sentences representing the dots shown, and finding the sums.

For one roll, have children draw the faces of the 3 dice and write the number model on an Exit Slip (Math Masters, page 305). Ask: Would the sum be the same if you added the numbers in a different order? Sample answer: Yes, it does not matter which order you add the numbers; you will still get the same sum.

� Math Boxes 3�10 INDEPENDENTACTIVITY

(Math Journal 1, p. 45)

Mixed Practice Math Boxes in this lesson are paired with Math Boxes in Lesson 3-13. The skills in Problem 4 preview Unit 4 content.

Writing/Reasoning Have children draw, write, or verbalize an answer to the following question: How do you find a missing number to make a sum of 10? A reasonable

answer should describe an addition strategy such as using 10 pennies or counting on a number line.

� Home Link 3�10 INDEPENDENTACTIVITY


Home Connection Children determine dime exchanges. They are asked to bring 10 dimes to school to add to their tool-kit coin collections.

� Minute Math+ WHOLE-CLASS ACTIVITY

Use Minute Math+, pages 10 and 46, to provide more practice with easy addition and subtraction concepts.

12 12

3

4567

8

9

101112 1

2

3

4567

8

9

1011

Draw the hour hand and the minute hand on each clock.3. 4.

half-past 7 o’clock half-past 3 o’clock

Note that Î means “penny,” Â means “nickel,” and Í means “dime.”

IMPORTANT: Please send 10 dimes with your child to class tomorrow.

Please return this Home Link to school tomorrow.

Family Note

Name Date

Dimes

1. How many? Î = 1 Â

Â = 1 Í

Î = 1 Í 2. How much money? ÂÂÎÎÎ = 13 ¢

ÎÂÂÂÎÎÎ = 19 ¢

ÂÂÂÂÂÂ = 30 ¢

1025

HOME LINK

3�10

Practice

EM3MM_G1_U03_51-90.indd 80 1/15/11 9:01 AM

Math Masters, p. 80

Home Link Master



More Frames and ArrowsLESSON

3 �9

Date

1. Fill in the frames.

2. Fill in the rule.

3. Fill in the rule and the frames.

4. Fill in the rule and the frames.

5. Make up your own.

15 30RuleCount by 5sAdd 5

20 18 16 14 12 10Rule

7 10 13Rule

90 80 70Rule

Rule

�

Sample answers given for Problems 2–4.

Answers vary.

2520 35 40

Subtract 2

16 19 22Add 3

60 50 40Subtract 10

EM3MJ1_G1_028-053_Unit3.indd 43 1/17/11 6:40 PM

Math Journal 1, p. 43

Student Page

NOTE Remember to allow time for the

Mental Math and Reflexes routine every day.

The skills addressed will help to develop

children’s problem-solving skills.

3 Differentiation Options

ENRICHMENT INDEPENDENTACTIVITY

� Checking Frames-and-Arrows 5–15 Min

Problems with a Calculator(Math Journal 1, p. 43)

Algebraic Thinking To further explore calculators, children use their calculators to check the Frames-and-Arrows problems on journal page 43. The first frame tells children which number to start with; the rule tells whether to enter + or – and which number to enter and count by.

EXTRA PRACTICE INDEPENDENTACTIVITY

� Skip Counting 5–15 Min


Have children count up and back on number lines to practice skip counting. For each number line, give oral directions to children telling them what to count by and whether to count up or back.

Name Date

LESSON

3�6 Using Number Lines

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EM3MM_G1_U03_51-90.indd 68 1/15/11 9:01 AM

Math Masters, p. 68

Teaching Master


counting with a calculator - everyday math - login€¢ count forward and backward by 1s, 2s, and 5s...

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