Multiplication Wrestling
Objectives To provide practice with extended multiplication
O
facts;
and to introduce the basic principles of multiplication
f
with multidigit numbers.
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Teaching the Lesson
Family
Letters
Assessment
Management
Common
Core State
Standards
Ongoing Learning & Practice
Key Concepts and Skills
Interpreting a Data Table
• Write numbers in expanded notation. Math Journal 1, p. 109
demonstration clock (optional) calculator (optional)
Students solve problems based on
data about recent U.S. presidents.
[Number and Numeration Goal 4]
• Add multidigit numbers. [Operations and Computation Goal 2]
• Use basic facts to compute extended facts. [Operations and Computation Goal 3]
• Solve multidigit multiplication problems. [Operations and Computation Goal 4]
• Evaluate numeric expressions containing
parentheses. [Patterns, Functions, and Algebra Goal 3]
• Use the Distributive Property of
Multiplication over Addition. [Patterns, Functions, and Algebra Goal 4]
Ongoing Assessment:
Informing Instruction See page 323.
Math Boxes 5 2
Math Journal 1, p. 110
Students practice and maintain skills
through Math Box problems.
Curriculum
Focal Points
Interactive
Teacher’s
Lesson Guide
Differentiation Options
READINESS
Reviewing Partial-Sums Addition
Math Masters, p. 141
Students practice the partial-sums
addition method.
ENRICHMENT
Judging a Multiplication Wrestling
Competition
Math Masters, p. 142
Students use estimation to determine the
winner of a Multiplication Wrestling
competition.
Ongoing Assessment:
Recognizing Student Achievement
Use Math Boxes, Problem 3. Key Activities
[Patterns, Functions, and Algebra Goal 2]
Students use their knowledge of extended
multiplication facts to play Multiplication
Wrestling. This game prepares students for
the partial-products algorithm, which will be
introduced in Lesson 55.
Study Link 5 2
Math Masters, p. 140
Students practice and maintain skills
through Study Link activities.
Ongoing Assessment:
Informing Instruction See page 322.
Materials
Student Reference Book, p. 253
Study Link 51
Math Masters, p. 488
transparency of Math Masters, p. 488
(optional) per partnership: 4 each of
number cards 0–9 (from the Everything Math
Deck, if available) or a ten-sided die slate index cards (optional)
Advance Preparation
For Part 1, make copies of Math Masters, page 488 (at least 1 per student). Make enough copies so that
some are always on hand for playing Multiplication Wrestling.
Teacher’s Reference Manual, Grades 4–6 pp. 9, 10, 126–132
320
Unit 5
Big Numbers, Estimation, and Computation
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Getting Started
Mental Math and Reflexes
Pose extended multiplication facts problems. Suggestions:
4 ∗ 50 = 200
30 ∗ 7 = 210
70 ∗ 8 = 560
20 ∗ 40 = 800
50 ∗ 40 = 2,000
90 ∗ 30 = 2,700
70 ∗ 800 = 56,000
600 ∗ 40 = 24,000
900 ∗ 900 = 810,000
Math Message
Study Link 5 1 Follow-Up
Use each of the numbers 2, 4, 6, and 8 to fill in the
blanks on the left side of the = sign so you get the largest
possible answer.
Students compare answers and review shortcuts
for solving multiplication problems in which one or
more of the factors is a multiple of 10.
(
+
)∗(
+
)=?
1 Teaching the Lesson
Math Message Follow-Up
SMALL-GROUP
DISCUSSION
Algebraic Thinking Have students share their solutions in small
groups. There are three possible combinations of the numbers:
(2 + 4) ∗ (6 + 8) = 84
(2 + 6) ∗ (4 + 8) = 96
(2 + 8) ∗ (4 + 6) = 100
Each of these combinations of numbers can be arranged in many
different ways because the order in which two numbers are added
or multiplied does not affect the answer (the turn-around rule).
The largest possible answer is 100.
Student Page
Games
Multiplication Wrestling
Playing Multiplication Wrestling
Materials 䊐 1 Multiplication Wrestling Worksheet for each player
(Math Masters, p. 488)
PARTNER
ACTIVITY
(Student Reference Book, p. 253; Math Masters, p. 488)
䊐 number cards 0–9 (4 of each) or 1 ten-sided die
Players
2
Skill
Partial-products algorithm
Object of the game To get the larger product of two 2-digit numbers.
Directions
1. Shuffle the deck of cards and place it number-side down on the table.
2. Each player draws 4 cards and forms two 2-digit numbers. Players
should form their 2 numbers so that their product is as large as possible.
Tell students that in this lesson they will learn to play a game
that provides computation practice. Players must calculate four
partial products and then find the sum of the partial products.
3. Players create 2 “wrestling teams” by writing each of their numbers as
a sum of 10s and 1s.
Review the rules of Multiplication Wrestling on Student Reference
Book, page 253 with the class.
6. To begin a new round, each player draws 4 new cards to form 2 new
numbers. A game consists of 3 rounds.
Links to the Future
Playing Multiplication Wrestling prepares students for the partial-products
algorithm, introduced in Lesson 5-5.
4. Each player’s 2 teams wrestle. Each member of the first team (for
example, 70 and 5) is multiplied by each member of the second team
(for example, 80 and 4). Then the 4 products are added.
5. Scoring: The player with the larger product wins the round and
receives 1 point.
Player 1: Draws 4, 5, 7, 8
Forms 75 and 84
Team 1
(70 ⫹ 5)
75 * 84
Team 2
(80 ⫹ 4)
*
Player 2: Draws 1, 9, 6, 4
Forms 64 and 91
Team 1
(60 ⫹ 4)
64 * 91
Team 2
(90 ⫹ 1)
*
Products: 70 * 80
70 * 4
5 * 80
5 *4
⫽ 5,600
⫽ 280
⫽ 400
⫽
20
Products: 60 * 90
60 * 1
4 * 90
4 *1
Total
(add 4 products)
5,000
1,200
⫹ 100
6,300
Total
(add 4 products)
75 * 84 ⫽ 6,300
⫽ 5,400
⫽
60
⫽ 360
⫽
4
5,000
700
120
⫹
4
5,824
64 * 91 ⫽ 5,824
Student Reference Book, p. 253
Lesson 5 2
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Game Master
Name
Date
Round 1
夹
Time
Multiplication Wrestling Record Sheet
Cards:
1 2
4 3
Adjusting the Activity
253
Numbers formed:
Acting out “tag team” wrestling may help students better understand the
rules of Multiplication Wrestling.
Using the example 75 ∗ 84, have students write each number as the sum of the
values of the digits: 70 + 5 and 80 + 4. Record 70 and 5 on separate index
cards of one color and 80 and 4 on separate index cards of another color.
Explain that 70 and 5 are one team, and 80 and 4 are a different team.
º
⫹
Teams: (
)º(
⫹
Products:
º
⫽
º
⫽
º
⫽
º
⫽
)
Total (add 4 products):
Round 2
Select four students to hold the cards. Remind students that in a tag-team
wrestling match, a person never wrestles someone from the same team. So, 70
and 5 cannot wrestle each other, nor can 80 and 4. Therefore, 70 wrestles 80
and then 4. Next, 5 wrestles 80 and then 4. Have students stand next to each
other as they “wrestle,” and record the product after each “wrestling match.”
Cards:
Numbers formed:
º
⫹
Teams: (
)º(
⫹
º
⫽
º
⫽
º
⫽
º
⫽
Products:
ELL
)
Total (add 4 products):
Round 3
Cards:
Numbers formed:
º
⫹
Teams: (
)º(
⫹
º
⫽
º
⫽
º
⫽
º
⫽
Products:
)
70
5
80
4
Total (add 4 products):
Math Masters, p. 488
Team 1
A U D I T O R Y
K I N E S T H E T I C
Team 2
T A C T I L E
V I S U A L
The record sheet on Math Masters, page 488 is designed to help
students organize and keep track of their computations. All
students should use this page to record their work for the first
3-round game they play.
Use a transparency of Math Masters, page 488 to demonstrate
how to fill in the record sheet. When they have learned the game,
many students will not need worksheets to record their results.
They may simply write their calculations on a blank sheet of
paper.
Student Page
Date
LESSON
5 2
䉬
Time
Presidential Information
The following table shows the dates on which the most recent presidents of the
United States were sworn in and their ages at the time they were sworn in.
President
F. D. Roosevelt
Date Sworn In
March 4, 1933
51
Truman
April 12, 1945
60
Eisenhower
January 20, 1953
62
Kennedy
January 20, 1961
43
Johnson
November 22, 1963
55
Nixon
January 20, 1969
56
Ford
August 9, 1974
61
Carter
January 20, 1977
52
Reagan
January 20, 1981
69
G. H. Bush
January 20, 1989
64
Clinton
January 20, 1993
46
G. W. Bush
January 20, 2001
54
Ongoing Assessment: Informing Instruction
Watch for students who correctly determine the partial products but then add
incorrectly. Encourage students to write their partial products so that the digits in
each number are aligned according to their value.
1
55ᎏ2ᎏ
1.
What is the median age (the middle age) of
the presidents at the time they were sworn in?
2.
What is the range of their ages (the difference
between the ages of the oldest and the youngest)?
3.
Who was president for the longest time?
4.
Who was president for the shortest time?
5.
Presidents are elected to serve for 1 term. A term lasts 4 years.
Which presidents served only 1 term or less than 1 term?
6.
Which president was sworn in about 28 years after Roosevelt?
7.
73
Age
Ask students about the patterns they noticed and the strategies
they used while playing and completing the record sheet. For
example, some students may note that for each set of four cards
drawn, there are many ways of forming 2-digit numbers. The goal
is to form two pairs that will yield the largest product.
years
26 years
F. D. Roosevelt
Ford
Kennedy, Ford, Carter, G. H. Bush
Kennedy
As of January 30, 2007:
Roosevelt was born on January 30, 1882.
125 years old
If he were alive today, about how old would he be?
Math Journal 1, p. 109
322
Unit 5 Big Numbers, Estimation, and Computation
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Student Page
2 Ongoing Learning & Practice
Date
Time
LESSON
Math Boxes
5 2
䉬
1.
Fill in the missing numbers on each number line.
a.
0.20
Interpreting a Data Table
INDEPENDENT
ACTIVITY
0.21 0.22 0.23 0.24 0.25 0.26 0.27 0.28 0.29
b.
2.6
2.61 2.62 2.63 2.64 2.65 2.66
(Math Journal 1, p. 109)
2.
Social Studies Link Students solve problems based on data
about the 12 most recent presidents of the United States.
Measure the line segment to the nearest
millimeter. Record the measurement in
millimeters and centimeters.
a.
About
b.
About
c.
About
3.
47 mm
4 cm 7 mm
4 . 7 cm
Ongoing Assessment: Informing Instruction
2.67
2.68 2.69
2.7
夹
Tell whether each number sentence is
true or false. Write T for true or F for
false.
T
a.
7.89 ⫺ 3.36 ⫽ 4.53
b.
12.6 ⫺ 4.8 ⫽ 3.9 ⫹ 3.9
c.
(4.6 ⫹ 2.9) ⫺ 3.1 ⬍ 3.7
d.
0.20 ⬎ 0.68 ⫺ (0.42 ⫹ 0.11)
T
F
T
34–37
148
128 129
4.
In Problem 4, watch for students who look only at the years of Ford’s and
Kennedy’s terms and therefore conclude that Kennedy was president for the
shortest time. Actually, Kennedy was president for a little more than 2 years
and 10 months, while Ford was president for less than 2 years and 6 months.
0.30
Insert ⬎ or ⬍ to make a true number
sentence.
a.
b.
c.
d.
5.
4,500,999 ⬎ 879,662
23,468,000 ⬎ 23,467,000
568,009,352 ⬍ 568,010,320
400,632 ⬎ 399,800
Divide mentally.
5
5
a.
45 / 9 ⫽
b.
450 / 90 ⫽
c.
1,000 / 200 ⫽
d.
e.
50
9
5
⫽ 2,000 / 40
⫽ 6,300 / 700
21
6
You may wish to use the context of journal page 109 to pose
word problems involving intervals of time. Students may use the
demonstration clock, calculators, or anything else that may help.
Some students may find it helpful to use an open number line to
illustrate the strategy of counting up in years, and possibly even
days. For the first suggestion given below, students might draw an
open number line like the one shown here. Students mark off the
starting year and count up in years, while recording the elapsed
time.
Math Journal 1, p. 110
20 yr
7 yr
1953
1960
9 yr
1980
1989
Have students record their answers on slates. Encourage students
to share their strategies. Suggestions:
●
●
How many years passed between the swearing in of
Eisenhower and the swearing in of G. H. Bush? 36 years
Between Carter and Reagan? 4 years
Approximately how much time passed between the swearing
in of Johnson and the swearing in of Nixon? 5 years, 59 days
Between Nixon and Ford? 5 years, 201 days
Study Link Master
Name
STUDY LINK
52
Date
Time
Extended Multiplication Facts
Solve mentally.
1.
3.
5.
17
27
42
2. 9 ∗ 3 =
420
270
6 ∗ 70 =
9 ∗ 30 =
420
270
60 ∗ 7 =
90 ∗ 3 =
60 ∗ 70 = 4,200
90 ∗ 30 = 2,700
600 ∗ 7 = 4,200
900 ∗ 3 = 2,700
60 ∗ 700 = 42,000
90 ∗ 300 = 27,000
32
3
= 15
4∗8=
4. 5 ∗
5 = 150
320
4 ∗ 80 =
30 ∗
320
50 = 1,500
40 ∗ 8 =
30 ∗
3 ∗ 50 = 150
40 ∗ 80 = 3,200
3,200
3 ∗ 500 = 1,500
400 ∗ 8 =
500 = 15,000
40 ∗ 800 = 32,000
30 ∗
6 times as many as 9.
54 is
6 times as many as 90.
540 is
60 times as many as 90.
5,400 is
9 .
540 is 60 times as many as
900 .
5,400 is 6 times as many as
54,000 is 6 times as many as 9,000 .
6∗7=
py g
g
p
Practice
6.
8.
15
4.26
= 6.3 + 8.7
7.
= 9.74 - 5.48
9.
7.36 + 2.14 =
1.8
9.5
= 4.6 - 2.8
Math Masters, p. 140
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Lesson 5 2
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Teaching Master
Name
LESSON
52
Example:
Date
Time
Math Boxes 5 2
Partial-Sums Addition
(Math Journal 1, p. 110)
10
Add the thousands:
Add the hundreds:
Add the tens:
Add the ones:
Find the total:
2,000
280
300
+ 42
2,000
500
120
+
2
2,622
INDEPENDENT
ACTIVITY
2,000 + 280 + 300 + 42 = ?
Mixed Practice Math Boxes in this lesson are paired
with Math Boxes in Lesson 5-4. The skill in Problem 5
previews Unit 6 content.
(200 + 300)
(80 + 40)
Solve each problem.
1,104
2.
= 600 + 180 + 40 + 12
4.
= 1,500 + 90 + 240 + 24
6.
800 + 120 + 160 + 24 =
1.
832
1,854
3.
5.
700 + 420 + 50 + 30 =
3,008
1,200
= 2,400 + 160 + 420 + 28
5,600 + 420 + 400 + 30 =
Ongoing Assessment:
Recognizing Student Achievement
6,450
Math Boxes
Problem 3
g
g
Use Math Boxes, Problem 3 to assess students’ ability to determine whether a
number sentence is true or false. Students are making adequate progress if they
can use mental arithmetic, a paper-and-pencil algorithm, or a calculator to
determine whether the number sentences are true or false. Some students may
be able to suggest how to change a false number sentence to make it true.
[Patterns, Functions, and Algebra Goal 2]
Study Link 5 2
Math Masters, p. 141
EM3cuG4MM_U05_139-176.indd 141
INDEPENDENT
ACTIVITY
(Math Masters, p. 140)
12/28/10 1:38 PM
Home Connection Students practice extended
multiplication facts.
3 Differentiation Options
READINESS
Reviewing Partial-Sums
Teaching Master
Name
LESSON
52
1.
Date
(Math Masters, p. 141)
Twelve players entered a Multiplication Wrestling competition. The numbers they
chose are shown in the following table. The score of each player is the product of
the two numbers. For example, Aidan’s score is 741, because 13 ∗ 57 = 741.
Which of the 12 players do you think has the highest score? Answers vary.
Group A
Group B
To explore partial-sums addition in preparation for adding partial
products in Multiplication Wrestling, have students find the
sum of four multidigit numbers. The problems are presented
horizontally to provide practice in correctly aligning the digits
in a vertical format.
Group C
Indira: 15 ∗ 73
Miguel: 17 ∗ 35
Colette: 13 ∗ 75
Jelani: 15 ∗ 37
Rex: 17 ∗ 53
Emily: 31 ∗ 75
Kuniko: 51 ∗ 37
Sarah: 71 ∗ 53
Gunnar: 31 ∗ 57
Liza: 51 ∗ 73
Tanisha: 71 ∗ 35
5–15 Min
Addition
Time
A Multiplication Wrestling Competition
Aidan: 13 ∗ 57
INDEPENDENT
ACTIVITY
Check your guess with the following procedure. Do not do any arithmetic for
Steps 2 and 3.
2.
3.
ENRICHMENT
In each pair below, cross out the player with the lower score. Find that
player’s name in the table above and cross it out as well.
Aidan; Colette
Indira; Jelani
Miguel; Rex
Emily; Gunnar
Kuniko; Liza
Sarah; Tanisha
Judging a Multiplication
Two players are left in Group A. Cross out the one with the lower score.
Two players are left in Group B. Cross out the one with the lower score.
Two players are left in Group C. Cross out the one with the lower score.
Wrestling Competition
Which 3 players are still left?
(Math Masters, p. 142)
Emily, Liza, and Sarah
4.
Of the 3 players who are left, which player has the lowest score?
Cross out that player’s name.
5.
There are 2 players left. What are their scores?
Who won the competition?
To apply students’ understanding of the Distributive
Property of Multiplication over Addition, have them use
estimation strategies to determine which player in a
Multiplication Wrestling competition has the highest score. On the
back of Math Masters, page 142, ask students to explain how they
solved Problem 4 and to show their work for Problem 5.
Liza’s is 3,723;
Sarah
Math Masters, p. 142
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5–15 Min
Emily
Sarah’s is 3,763.
6.
INDEPENDENT
ACTIVITY
12/28/10 1:38 PM
Unit 5 Big Numbers, Estimation, and Computation
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Name
STUDY LINK
52
Date
Time
Extended Multiplication Facts
Solve mentally.
17
1.
3.
6∗7=
2.
6 ∗ 70 =
9 ∗ 30 =
60 ∗ 7 =
90 ∗ 3 =
60 ∗ 70 =
90 ∗ 30 =
600 ∗ 7 =
900 ∗ 3 =
60 ∗ 700 =
90 ∗ 300 =
4∗8=
4.
5∗
= 15
4 ∗ 80 =
30 ∗
= 150
40 ∗ 8 =
30 ∗
= 1,500
40 ∗ 80 =
∗ 50 = 150
400 ∗ 8 =
∗ 500 = 1,500
40 ∗ 800 =
5.
9∗3=
54 is
30 ∗
= 15,000
times as many as 9.
540 is
times as many as 90.
5,400 is
times as many as 90.
.
5,400 is 6 times as many as
.
54,000 is 6 times as many as
.
Practice
6.
= 6.3 + 8.7
7.
8.
= 9.74 - 5.48
9.
7.36 + 2.14 =
Copyright © Wright Group/McGraw-Hill
540 is 60 times as many as
= 4.6 - 2.8
140
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