# 1 materials Teaching the Lesson

```Objective
To demonstrate the use of decimal notation for metric
measures and the conversion of centimeters to meters.
1
materials
Teaching the Lesson
Key Activities
Children use metric units of length to model decimals through hundredths.
Key Concepts and Skills
ⵧ Math Journal 1, p. 119
ⵧ Student Reference Book,
pp. 218 and 219
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• Use base-10 blocks and a meterstick to model tenths and hundredths.
• Use base-10 blocks and a meterstick to represent, compare, and order decimals through
hundredths. [Number and Numeration Goal 6]
ⵧ slates, tape
ⵧ metersticks (1 per partnership, plus
3–4 more for meterstick “shelf,” if
available)
ⵧ base-10 blocks: longs and cubes
Key Vocabulary decimeter
[Number and Numeration Goal 1]
• Find fractional parts of a region using a meterstick and base-10 blocks.
[Number and Numeration Goal 2]
Ongoing Assessment: Recognizing Student Achievement Use journal page 119.
[Number and Numeration Goal 6]
2
Ongoing Learning & Practice
Children simulate a shopping trip to practice calculating money.
Children practice and maintain skills through Math Boxes and Home Link activities.
3
Children review metric units of measure.
They estimate and measure the lengths of
objects.
ⵧ Math Journal 1, p. 120
ⵧ Student Reference Book,
pp. 215–217
ⵧ Home Link Master (Math Masters,
p. 148)
ⵧ Teaching Master (Math Masters,
p. 147)
ⵧ calculator and bills and coins
(optional)
materials
Differentiation Options
materials
ENRICHMENT
Children explain decimal relationships.
Advance Preparation Tape together two or three metersticks and make a 1-meter-long shelf
by taping the bundle to the board, centimeter side facing outward. See margin on page 365.
ⵧ Math Journal 1, p. 60
ⵧ Student Reference Book, p. 141
ⵧ rulers, metersticks, tape measures
ⵧ half-sheets of paper and
base-10 blocks
Technology
Assessment Management System
Journal page 119
See the iTLG.
Lesson 5 9
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363
Getting Started
Mental Math and Reflexes
Math Message
Display the following sets of base-10 blocks or use
base-10 shorthand to indicate the blocks. On slates,
children write a decimal to represent the base-10 blocks shown
Turn to pages 218 and 219 in your Student
Reference Book. What is the maximum length for a python?
䉬
7 longs 0.7; seven tenths
1 long and 8 cubes 0.18; eighteen hundredths
9 cubes 0.09; nine hundredths
2 longs and 1 cube 0.21; twenty-one hundredths
1 flat, 1 long, 1 cube 1.11; one and eleven hundredths
Partners orally read their counts to each other from
Problems 8 and 9. Encourage them to extend the
counts through whole numbers.
2 flats, 3 longs, 4 cubes 2.34; two and thirty-four hundredths
1 Teaching the Lesson
䉴 Math Message Follow-Up
WHOLE-CLASS
DISCUSSION
(Student Reference Book, pp. 218 and 219)
The maximum length of a python is 9 meters. Ask children to
state the maximum length for each of the other animals. Show
children a meterstick as a frame of reference. Be sure that they
state a unit with each measurement; some of the measurements
are reported in meters and others in centimeters.
Use the information on Student Reference Book, pages 218 and
Student Page
●
Which is the longest animal? python
●
Which is the shortest? Queen termite
●
Which is longer, the green turtle or the Mississippi alligator?
Mississippi alligator
●
Which is longer, the agama lizard or the Mississippi alligator?
Mississippi alligator
Data Bank
Animal Clutches
All of the animals shown lay eggs. A nest of eggs is
called a clutch.
Most birds, reptiles, and amphibians lay eggs once or
twice a year. Insects may lay eggs daily during a certain
season of the year.
NOTE If children disagree on some of their answers or comparisons, it is most
likely due to the inconsistent units (cm and m). Record their ideas on the board,
and resolve their differences at the end of the lesson.
Green Turtle
up to 1.5 meters long
median of 104 eggs,
as many as 184 eggs
Pose ratio-comparison questions, such as:
• About how many times longer is the green turtle than the giant toad? 5 times
Ostrich
more than 2 meters tall
• About how many times longer is the python than the Mississippi alligator?
2 times
up to 15 eggs
A U D I T O R Y
up to 30 cm long
maximum of 35,000 eggs
Student Reference Book, p. 218
364
Unit 5 Place Value in Whole Numbers and Decimals
䉬
K I N E S T H E T I C
䉬
T A C T I L E
䉬
V I S U A L
䉴 Exploring Decimals in
WHOLE-CLASS
ACTIVITY
Metric Units
1. Show the class a meterstick, or point out the meterstick shelf
mounted on the board. Explain that in previous lessons, a
base-10 block flat was the ONE. For this lesson, a meter will
be the ONE. All the fractions and decimals will be parts of a
meter.
2. Place a long on the meterstick shelf so that one end is at the
0-mark. Ask: How many centimeters are in one long? 10
A meterstick shelf
NOTE A decimeter is equivalent to 10 cm. Decimeters (dm) are not used as
commonly as some other metric units of length (mm, cm, m, km).
3. Ask a volunteer to put enough longs on the meterstick shelf to
reach the one-meter mark. How many longs are in 1 meter? 10
1
What fraction of 1 meter is 1 long? 1
0 Write 1 long (10 centimeters) 0.1 meter on the board.
4. Draw a number line under the meterstick while children count
in unison: 1-tenth, 2-tenths, ... Remind them that each long is
1
meter.
10
Meterstick
0
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
1 long 0.1 of a meter
5. Replace the long at the 0-mark on the meterstick with cubes.
How many cubes would be needed to reach the 1-meter mark?
100 How many centimeters are in 1 meter? 100 What fraction
1
of 1 meter is 1 centimeter? 100 Write 1 cube (1 centimeter) 0.01 meter on the board.
6. Make a chalk mark on the board above the 24-cm mark. Ask
someone to place longs and cubes on the meterstick from the
0-cm to the 24-cm mark. 2 longs and 4 cubes How many
hundredths of a meter does this show? 24 How would you write
this as a decimal? 0.24 meter
Record the information in a table on the board.
length in centimeters
longs
cubes
length in meters
24 cm
2
4
0.24 m
ELL
the Activity
Make and display a Metric Equivalencies
chart in the classroom.
Metric Equivalencies
10 centimeters = 0.1 meter
1 centimeter = 0.01 meter
AUDITORY
䉬
KINESTHETIC
䉬
TACTILE
䉬
VISUAL
Erase the chalk mark above the 24-centimeter mark. Repeat this
routine with several other measurements. Include measurements
that result in decimals with zeros in the tenths or hundredths
places, such as 70 cm and 6 cm.
Lesson 5 9
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365
Student Page
Date
Time
LESSON
䉴 Writing Metric Measurements in
Decimals for Metric Measurements
5 9
䉬
1. Fill in the missing information. Put longs and cubes end to end on a meterstick
Length in
Centimeters
Number
of Longs
Number
of Cubes
Length
in Meters
2
3
4
6
cm
0
3
cm
0
3
8
0
0.24 m
0.36 m
0.03 m
0.08 m
cm
4
3
24 cm
36 cm
3
8 cm
30
43
0.3 m
0.43 m
PARTNER
ACTIVITY
Decimal Notation
(Math Journal 1, p. 119)
Children model and compare metric measurements by sharing
metersticks and base-10 blocks with partners. They write the
measurements as decimals and label a centimeter ruler for
measurements given in decimal notation.
Work with a partner. Each partner uses base-10 blocks to make one length
in each pair. Compare the lengths and circle the one that is greater.

2. 0.09 or 0.12

3. 0.24 or 0.42
5. 0.18 or 0.5
4. 0.10 or 0.02
6. 0.2 or 0.08
Ongoing Assessment:
Recognizing Student Achievement
7. 0.3 or 0.24
Follow these directions on the ruler below. Use base-10 blocks and a
8. Make a dot at 4 cm and label it with the letter A.
9. Make a dot at 0.1 m and label it with the letter B.
10. Make a dot at 0.15 m and label it with the letter C.
11. Make a dot at 0.08 m and label it with the letter D.
A
0
1
2
3
4
D
5
6
7
B
8
9
C

Journal
Page 119
Problems 2–4
Use journal page 119 to assess children’s progress in comparing decimals.
Children are making adequate progress if they successfully complete Problems
2, 3, and 4 with or without manipulatives. Some children may be able to
complete Problems 5, 6, and 7 with or without manipulatives.
[Number and Numeration Goal 6]
10 11 12 13 14 15
cm
Math Journal 1, p. 119
2 Ongoing Learning & Practice
NOTE Some children may prefer to use the
flat as the ONE, rather than the meter, to
complete Problems 2–7 on journal page 119.
䉴 Simulating a Shopping Trip
PARTNER
ACTIVITY
(Math Masters, p. 147; Student Reference Book, pp. 215–217)
This activity was introduced in Lesson 1-11. To buy items
on the shopping trip, children can use either the Variety
Store Poster, or one of the two Stock-Up Sale Posters in
the Student Reference Book.
Teaching Master
Name
Date
LESSON
Time
A Shopping Trip
59
䉬
Use pages 215–217 in your Student Reference Book.
1. List at least 4 items you are buying in the space below. If you buy
the same item 2 times, list it 2 times.
Item
Children select the items they want to buy; record the information
on Math Masters, page 147; and estimate the number of bills to
give the shopkeeper. They take turns acting out the transactions
with bills and coins. After each partner completes the shopping
trip, they work together to complete the Try This problem.
Sale Price
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䉴 Math Boxes 5 9
䉬
INDEPENDENT
ACTIVITY
(Math Journal 1, p. 120)
2. Estimate how many dollar bills you need to pay for these items.
Mixed Practice Math Boxes in this lesson are paired with
Math Boxes in Lesson 5-11. The skill in Problem 6
previews Unit 6 content.
3. Give the clerk the dollar bills.
4. The clerk calculates the total cost. \$
5. The clerk calculates the change you should get. \$
Î, Â, Í, ‰.
Try This
Use Stock-Up Sale Poster #1 in your Student Reference Book, page 216.
7. Justin wants to buy 5 ballpoint pens. How much money will he save by
buying them at the “5-or-More Sale”?
Regular price (for 5 ballpoint pens): \$
“5-or-More Sale” price:
\$
Amount saved:
\$
1.95
1.35
0.60
Writing/Reasoning Have children write an answer to the
following: Explain why the area in Problem 4 is measured
in square units. Sample answer: The area of the rectangle
is covered with squares. I counted 21 squares so the area is 21
square units.
Math Masters, p. 147
366
Unit 5 Place Value in Whole Numbers and Decimals
Student Page
INDEPENDENT
ACTIVITY
䉬
(Math Masters, p. 148)
Date
Time
LESSON
Math Boxes
5 9
䉬
Write the number that has
6 in the ones place
4 in the tenths place
3 in the hundredths place
2 in the thousandths place
1.
Home Connection Children fill in missing decimal
numerals on number lines and mark metric measures on
a ruler.
2.
If each grid is ONE, what part of
each grid is shaded? Write the
decimal.
6.4 3 2
0.25
35
complete these problems on your
calculator.
3.
Enter
3 Differentiation Options
䉴 Reviewing Metric Measure
INDEPENDENT
ACTIVITY
1,366
966
627,581
628,581
43,775
43,175
33–35
Draw a 3 7 rectangle.
How?
12,000
400
1,000
600
37
21 square units
Number model:
Area:
21
18 19
154–156
6.
Draw an example of a cylinder.
4,000,000
3,000
1
1 means
60,000
6 means
9 means 900,000
4 means
5–15 Min
3 means
To explore metric units of length and how to measure,
have children estimate and measure the lengths of objects
in the room. Children turn to page 141 in their Student
Reference Books to review the relative size of millimeters,
centimeters, and meters. After a brief review, have children use
their personal references (Math Journal 1, page 60) to estimate
the length of objects in the room to the nearest centimeter and
meter and then measure the object to check their estimate. On a
half-sheet of paper, children can make a table, such as the one
below, to record their work. Have children describe the objects
they measured. Encourage vocabulary like shorter, longer,
estimate, actual, and so on.
My Estimate
12,894
For the number 4,963,521
5.
(Math Journal 1, p. 60; Student Reference Book, p. 141)
Object
Change to
894
4.
0.07
Peanut
Butter
Jar
18–21
112–114
Math Journal 1, p. 120
Actual Length
Name
Date
59
Family
Note
ENRICHMENT
Your child has been using the metric system to practice measurements and to
convert centimeters to meters. The following equivalencies will assist you in
helping your child solve Problems 3–6.
1 cm 10 mm
1 m 100 cm
1 m 1,000 mm
INDEPENDENT
ACTIVITY
Fill in the missing numbers.
5–15 Min
2.
Hundredths
To apply children’s understanding of tenths and
hundredths, have them write a response to the following
question: Vanna says that 0.10 m is more than 0.2 m
because 0.10 m is 10 longs but 0.2 m is only 2 longs. How could
you help Vanna see her mistake? Supply base-10 blocks and
metersticks for children to use as needed. Sample answer: 0.10
represents 1 tenth and 0 hundredths, or 1 long; 0.2 represents
2 tenths and 0 hundredths, or 2 longs. So, 0.2 is more than 0.10.
Time
Practice with Decimals
䉬
137–140
1.
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.7
0.8
0.9
1.0
1.1
1.2
1.3
1.4
1.5
Follow these directions on the ruler below.
3. Make a dot at 7 cm and label it with the letter A.
4. Make a dot at 90 mm and label it with the letter B.
5. Make a dot at 0.13 m and label it with the letter C.
6. Make a dot at 0.06 m and label it with the letter D.
0
1
2
3
4
5
D
•
A
•
6
7
B
•
8
C
•
9
10 11 12 13 14 15
cm
Practice
7. 3 9 10.
12
27
26
8. 5 8 11.
9
40
9. 0 8 33
12.
15
0
53
Math Masters, p. 148
Lesson 5 9
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367
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