EM3cuG4TLG1 163 U03L02 - Everyday Math · • Find factors and multiples of numbers. [Number and...
Transcript of EM3cuG4TLG1 163 U03L02 - Everyday Math · • Find factors and multiples of numbers. [Number and...
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eToolkitePresentations Interactive Teacher’s
Lesson Guide
Algorithms Practice
EM FactsWorkshop Game™
AssessmentManagement
Family Letters
CurriculumFocal Points
Common Core State Standards
Lesson 3�2 163
Advance PreparationFor Part 1, have plastic bags or envelopes available for storing the Fact Triangles. Think about how to pair
students for this activity so they will be at similar skill levels.
Teacher’s Reference Manual, Grades 4–6 pp. 16, 79, 80, 267–269
Key Concepts and Skills• Find factors and multiples of numbers.
[Number and Numeration Goal 3]
• Identify prime and composite numbers.
[Number and Numeration Goal 3]
• Identify square numbers.
[Number and Numeration Goal 4]
• Solve multiplication facts.
[Operations and Computation Goal 3]
• Identify and use patterns in the
Multiplication/Division Facts Table.
[Patterns, Functions, and Algebra Goal 1]
Key ActivitiesStudents cut out Multiplication/Division Fact
Triangles. They discuss the Multiplication/
Division Facts Table, symbols, and
vocabulary for multiplication. Students
identify prime and composite numbers. They
use Fact Triangles to maintain automaticity
with multiplication facts.
Key Vocabularymultiplication facts � factors � products �
factor pair � multiples � square numbers �
turn-around facts � prime number �
composite number
MaterialsMath Journal 1, inside front cover; p. 56;
Activity Sheets 1–4 � Student Reference
Book, pp. 8, 178A, and 178B � Study Link 3�1
transparencies of Math Masters, pp. 408
and 409 (optional) � paper clips � envelopes
or resealable plastic bags � scissors �
calculator � counters (optional)
Playing Name That NumberStudent Reference Book, p. 254
Math Masters, p. 489
deck of number cards (the Everything
Math Deck, if available)
Students practice representing
numbers in different ways.
Ongoing Assessment: Recognizing Student Achievement Use Math Masters, page 489. [Number and Numeration Goal 4]
Math Boxes 3�2Math Journal 1, p. 57
Students practice and maintain skills
through Math Box problems.
Study Link 3�2Math Masters, p. 75
Students practice and maintain skills
through Study Link activities.
READINESS
Making Rectangular ArraysMath Masters, p. 76
centimeter cubes � 4 each of number cards
1–10 (from the Everything Math Deck, if
available)
Students practice multiplication facts using
a concrete model.
EXTRA PRACTICE
Playing Buzz and Bizz-BuzzStudent Reference Book, p. 234
Students practice naming multiples.
ELL SUPPORTBuilding a Math Word BankDifferentiation Handbook, p. 140
Students add the term square numbers
to their Math Word Banks.
Teaching the Lesson Ongoing Learning & Practice
132
4
Differentiation Options
Multiplication FactsObjectives To review strategies for solving multiplication facts;
to help students maintain automaticity with multiplication facts;
and to introduce prime and composite numbers.
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164 Unit 3 Multiplication and Division; Number Sentences and Algebra
1 Teaching the Lesson
� Math Message Follow-Up WHOLE-CLASSDISCUSSION
Tell the class they will use Fact Triangles to practice multiplication facts and another tool, the Multiplication/Division Facts Table, to discuss the terms factor, product, and multiple.
� Reviewing the Multiplication/ WHOLE-CLASSDISCUSSION
Division Facts Table(Math Journal 1, inside front cover; Math Masters, p. 408)
Introducing the Symbols º and /Ask students to look at the inside front cover of Math Journal 1. Display an overhead transparency of Math Masters, page 408. Remind students of the following:
� The table shows the multiplication facts.
� The 0s facts have been omitted to avoid confusion about division by 0 (which is not possible).
� The 10s facts are included.
Point out the ∗ and / symbols in the upper left-hand corner of the table. Explain that in Grades 4, 5, and 6 of Everyday Mathematics, an asterisk (∗) is usually used to indicate multiplication. A slash (/) is often used to indicate division, but the ÷ and the �
_ RR symbols are also used.
NOTE The symbols ∗ and / are used for multiplication and division on computer
keyboards. The asterisk helps avoid confusion between the × symbol and the
variable x in algebra. Using the slash for division clearly relates division to
fractions. 1 / 2, 1
_ 2 , 1 ÷ 2, and 2 �
_ 12 all represent the same number.
ELL
Getting Started
Math Message Cut apart the Multiplication/Division Fact Triangles on Activity Sheets 1–4 at the back of your journal. Write your initials on the back of each one.
Put the Fact Triangles and two paper clips into a plastic bag or envelope.
Study Link 3�1 Follow-Up Have partners discuss the pattern in Problem 1 and explain why the numbers will always change from odd to even or even to odd when moving from the in column to the out column.
Mental Math and Reflexes In preparation for discussing multiples, pose calculator skip-counting problems, starting with 0. Suggestions:
20s 0, 20, 40, 60, 80, 100, ...
50s 0, 50, 100, 150, 200, 250, ...
6s 0, 6, 12, 18, 24, 30, ...
8s 0, 8, 16, 24, 32, 40, ...
Back by 4s 0, -4, -8, -12, -16, -20, ...
Back by 7s 0, -7, -14, -21, -28, -35, ...
1
1 2 3 4 5 6 7 8 9 10
1 10
2 4
7
8
9
10
3 9
4 16
5 25
6 36
49
64
81
908070605040302010
20
30
24 40
50
60
70
80
90
100
squarenumbers
factor
factor product
multiplesof 10
multiples
of 10
∗,/
Multiplication/Division Facts Table from the inside front
cover of Math Journal 1 and Math Masters, page 408
NOTE For Multiplication/
Division Fact Triangles and
a Facts Table with facts
through 12 º 12, see
www.everydaymathonline.com.
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Reviewing the Meaning of Factors, Products, and MultiplesRemind students that the numbers in the shaded row and shaded column in the table are called factors, and the rest of the numbers are called products. For example, in 4 ∗ 6 = 24, 4 and 6 are factors of 24, and 24 is the product of 4 and 6. 4 and 6 are a factor pair of 24. A number may have more than one factor pair. For example, the factor pairs for 24 are 1 and 24, 2 and 12, 3 and 8, and 4 and 6. To support English language learners, label and identify the factors and products on the transparency of Math Masters, page 408 as students do so on the inside front cover of Math Journal 1.
Direct students to look across a row or down a column to find the multiples of a number. The multiples of 10, for example, are 10, 20, 30, 40, and so on. Point out that a whole number is a multiple of each of its factors.
Reviewing Square NumbersNext point out the shaded products on the diagonal. Remind students that these products are called square numbers. Each square number is the product of a counting number multiplied by itself. For example, 9 is a square number, because 3 ∗ 3 = 9.
Reviewing Turn-Around FactsPoint out that the products above the diagonal of square numbers are “mirror images” of the products below the diagonal. For example, 6 ∗ 3 and 3 ∗ 6 both equal 18. These are called turn-around facts. If you know a fact, you also know its turn-around fact. To support English language learners, ask: Why do you think these facts are called turn-around facts?
Reviewing Other Multiplication ShortcutsAsk students if they know any other multiplication shortcuts. For example:
� 0 times any number equals 0.
� 1 times any number equals the number.
� To find 2 times a number, double the number.
� To find 10 times a number, write 0 after the number.
� Factors Pairs of Prime WHOLE-CLASS ACTIVITY
Numbers(Student Reference Book, p. 8; Math Journal 1, p. 56;
Math Masters, p. 409)
On the board, draw the Fact Triangle in the margin, or fill in the numbers on a transparency of Math Masters, page 409.
Have students identify the product and the factors. Product: 2. Factors: 1, 2. Point out that every Fact Triangle illustrates a factor pair of the product. For example, the Fact Triangle in the margin shows that 1 and 2 make up a factor pair of the product, 2.
Lesson 3�2 165
Adjusting the Activity
Have students find common multiples of 2
and 3 or common multiples of 2, 3, and 5 and
organize them in Venn diagrams. For example:
ELL
Multiplesof 5
Multiplesof 3
Multiplesof 2
2
22
26
10 6 12
30
15
935
14
4 8
16
28
20 18 24
272125
Multiplesof 2
Multiplesof 3
2 4
8 10
14 16
6 3 9
1512
18
AUDITORY � KINESTHETIC � TACTILE � VISUAL
•
1 2
2
∗, /
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166 Unit 3 Multiplication and Division; Number Sentences and Algebra
Then have students complete Problem 1 on journal page 56. They may use their Fact Triangles or a Multiplication/Division Facts Table. Ask students to name the numbers in the table that have only one factor pair. 2, 3, 5, 7, and 11 Explain that there is a name for numbers that have only one factor pair. Ask: Does anyone know what these numbers are called? Prime numbers List the prime numbers on the board along with their factor pairs:
Prime Number Factor Pair
2 1 and 2
3 1 and 3
5 1 and 5
7 1 and 7
11 1 and 11
Ask students if they notice anything about the factor pairs of the prime numbers. If no one suggests it, point out that each factor pair consists of 1 and the original number. Explain that a counting number is a prime number if it has exactly two factors: 1 and itself.
Next, ask students to name the numbers that are not prime. 4, 6, 8, 9, 10, and 12 Tell students that these are called composite numbers. A composite number is a counting number with more than two factors. Composite numbers have at least two factor pairs.
For more information about prime and composite numbers, students can refer to Student Reference Book, page 8. Ask students to complete journal page 56.
� Reviewing the Models WHOLE-CLASS ACTIVITY
of Multiplication(Student Reference Book, pp. 178A and 178B)
Tell students that thinking about what a multiplication fact means can help them figure out facts they can’t remember. For example, a student who could not remember the answer to 7 ∗ 6 could think about this fact in several ways:
� Equal groups: How many objects are in 7 groups of 6?
� Arrays or area: How many objects are in an array with 7 rows and 6 objects in each row?
� Multiplicative comparison: What number is 7 times as many as 6?
These interpretations are described on Student Reference Book, pages 178A and 178B.
Suggest additional facts and have students record the corresponding questions on their slates. For example:
● 8 ∗ 7 ● 9 ∗ 4 ● 6 ∗ 9
Date Time
Factor Pairs of Prime NumbersLESSON
3�2 8
1. In the table below, list all the factor pairs of each number.
Number Factor Pairs
2 1 and 2
3
4
5
6 1 and 6 2 and 3
7
8
9
10
11
12
2. Name a number in the table above that is not a prime number. Explain how you
know it is not prime.
3. Name at least three prime numbers that are not in the table above.
4. Choose one of your answers from Problem 3. Explain how you know it is a
prime number.
1 and 3
1 and 5
1 and 7
1 and 11
1 and 4; 2 and 2
1 and 8; 2 and 4
1 and 9; 3 and 3
1 and 10; 2 and 5
1 and 12; 2 and 6; 3 and 4
Sample answer: 12; it has three factor pairs: 1 and
12, 2 and 6, and 3 and 4. A prime number has only one factor pair.
Sample answers: 13, 17, 19
Sample answer: 13 is a prime number because its
only factor pair is 1 and 13.
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Math Journal 1, p. 56
Student Page
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2 Ongoing Learning & Practice
� Playing Name That Number PARTNER ACTIVITY
(Student Reference Book, p. 254; Math Masters, p. 489)
Students play Name That Number to practice representing numbers in different ways. See Lesson 2-2 for additional information.
Ongoing Assessment: Math Masters
Page 489
� Recognizing Student Achievement
Use Math Masters, page 489 to assess students’ ability to use
numerical expressions involving one or more of the basic four arithmetic
operations to give equivalent names for whole numbers. Students are making
adequate progress if they are able to create numerical expressions to name the
target number for two rounds of play. Some students may write numerical
expressions that include parentheses or exponents.
[Number and Numeration Goal 4]
Date Time
Math Boxes LESSON
3 �2
3. Earth is covered by a rocky outer layer called the
crust, which is made up of many elements.
a. Is there more aluminum or silicon in Earth’s crust?
b. What percentage of Earth’s crust is aluminum?
c. Which element makes up most of Earth’s crust?
oxygen
8%
silicon
Oxygen
47%Silicon
28%
Iron, Calcium,
Sodium,
Potassium,
Others
17%
Aluminum
8%
Elements Found in Earth’s Crust(percent by weight)
1. The numbers 28, 35, and 42 are all
multiples of __. Circle the best answer.
A 7
B 4
C 6
D 2
2. Complete the “What’s My Rule?” table
and state the rule.
Rule: �95
9 162–166
in out
236 331
682 777
391 486
938
647 742
A B C D
5. Put these numbers in order from smallest
to largest.
0.6 0.06 0.43 0.9
0.9
0.6
0.43
0.06
32 3390
4. Name as many line segments as you can
in the figure below.
AB���, AC���, AD���, BC���, BD���, CD���
1,033
Math Journal 1, p. 57
Student Page
Lesson 3�2 167
�� ��
�, �
“6 times 7 equals what number?” or
“What number is 6 times as many as 7?”
� Sorting Fact Triangles PARTNER ACTIVITY
(Math Journal 1, inside front cover; Math Masters, p. 409)
Ask students to count the Fact Triangles they stored—there should be 36.
Draw a large Multiplication/Division Fact Triangle on the board, or display a transparency of Math Masters, page 409, with numbers inserted. Remind students that the numbers in the bottom corners of the triangle are factors and that the number under the dot is the product of the two factors. Demonstrate how to use the Fact Triangle by covering the product.
Divide the class into partnerships. As students practice their facts, remind them to sort the Fact Triangles into two piles —“OK” and “Try Again”—as they did with the +, - Fact Triangles in Unit 1.
Use this Fact Triangle session to screen the class to determine which students are proficient with the basic multiplication facts. Students with triangles in the “Try Again” pile will need additional support. Games and Fact Triangles are available to provide opportunities for students to practice these facts. See the Teacher’s Reference Manual for ideas on establishing a game routine in your classroom. Students identified in this initial screening as needing additional support should participate in the 50-Facts Test routine throughout the year. See Lesson 3-3 for more information.
Adjusting the Activity
Encourage the use of tools and strategies,
such as:
� counters or pictures to illustrate facts,
� calculators for skip counting to find
products, and
� the Multiplication/Division Facts Table to
find products.
ELL
AUDITORY � KINESTHETIC � TACTILE � VISUAL
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168 Unit 3 Multiplication and Division; Number Sentences and Algebra
3 Differentiation Options
READINESS PARTNER ACTIVITY
� Making Rectangular Arrays 5–15 Min
(Math Masters, p. 76)
To provide experience with multiplication facts using a concrete model, have students make rectangular arrays with centimeter cubes and record a number model for each array.
EXTRA PRACTICE SMALL-GROUP ACTIVITY
� Playing Buzz and Bizz-Buzz 5–15 Min
(Student Reference Book, p. 234)
To practice naming multiples, have students play Buzz and Bizz-Buzz. Before playing the game, remind students that a whole number is a multiple of each of its factors.
ELL SUPPORT SMALL-GROUP ACTIVITY
� Building a Math Word Bank 5–15 Min
(Differentiation Handbook, p. 140)
To provide language support for multiplication, have students use the Word Bank Template found on Differentiation Handbook, page 140. Ask students to write the term square numbers, draw pictures relating to the term, and write other related words. See the Differentiation Handbook for more information.
LESSON
3�2
Name Date Time
Rectangular Arrays
7
Rectangular arrays can be used to model multiplication facts.
Follow these steps to build arrays with centimeter cubes.
1. Place a deck of number cards (1�10) facedown on the table.
Turn over 2 cards.
◆ Use one card for the number of rows in the array.
◆ Use the other card for the number of cubes in each row.
2. Use centimeter cubes to build the array.
Example:
If and are turned
over, you can make either array:
3. Record some of the arrays you made in the table below.
2
2
4
4
2 rows,
4 cubes per row
4 rows,
2 cubes per row
How many How many cubes How many Number rows? in each row? cubes in all? model
4 2 8 4 º 2 � 8
Math Masters, p. 76
Teaching Master
STUDY LINK
3�2 Multiplication Facts 16 20
Name Date Time
1 6
2
7
8
9
3 3 9
4 8
5
6
14
1 2 3 4 5 7 8 9 10
10 10 40 50 60 70 80 9020 30 100
2 4 6 8 10 12 14 16 18 20
6 12 15 18 21 24 27 30
4 12 16 20 24 28 32 36 40
5 10 15 20 25 30 35 40 45 50
6 12 18 24 30 36 42 48 54 60
7 21 28 35 42 49 56 63 70
8 32 40 48 5616 24 64 72 80
9 36 45 54 63 7218 27 81 90
1 2 3 4 5 6 7 8 9 10º, /
1. Complete the Multiplication/Division Facts Table below.
2. List all the factors of 36.
3. List the factor pairs of 16. and , and , and
4. Name the product of 8 and 7.
5. Name four multiples of 4. , , , 2420168
56
4482161
1, 2, 3, 4, 6, 9, 12, 18, 36
Practice
Sample answers:
6. � 91 � 38 7. � 630 � 242 8. 1,462 � 697 � 76538853
Math Masters, p. 75
Study Link Master
NOTE For practice with
facts through 12 º 12, have
students use the Online Master at
www.everydaymathonline.com
in place of Study Link 3�2.
� Math Boxes 3�2 INDEPENDENTACTIVITY
(Math Journal 1, p. 57)
Mixed Practice Math Boxes in this lesson are paired with Math Boxes in Lesson 3-4. The skill in Problem 5 previews Unit 4 content.
� Study Link 3�2 INDEPENDENTACTIVITY
(Math Masters, p. 75)
Home Connection Students complete a Multiplication/Division Facts Table and name factors, products, and multiples of numbers.
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