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Grade 2
Reteach
Chapter 1
Name Co
pyri
ght
© T
he M
cGra
w-H
ill C
ompa
nies
, Inc
. Per
mis
sion
is g
rant
ed t
o re
prod
uce
for
clas
sroo
m u
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Lesson 1 Reteach
Addition Properties
2 + 3 = 5
4 + 0 = 4
3 + 2 = 5 0 + 4 = 4
The order of the addends Add 0 to a number. The sumchanged. The sum is the same. is the same as the other addend.
Find each sum.
1. 8 + 4 =
12
4 + 8 = 12
3. 3 + 4 =
4 + 3 =
5. 5 + 3 =
3 + 5 =
2. 5 + 0 =
0 + 5 =
4. 1 + 8 =
8 + 1 =
6. 6 + 5 =
5 + 6 =
Grade 2 • Chapter 1 Apply Addition and Subtraction Concepts 3
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The McG
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ill Companies, Inc. Perm
ission is granted to reproduce for classroom use.
Lesson 2 Reteach
Count On to Add
You can use squares to count on.
Find 5 + 3. Start at 5. Count on 3.
1 2 3 4 5 6 7 8 5 + 3 = 8 5
+ 3
8
Use the squares. Add squares to count on.
1. 8 + 1 = 9
2. 6 + 2 =
3. 7 + 3 =
4. 5 + 1 =
5. 9 + 3 =
6. 7 + 2 =
7. 6 + 3 = 4 Grade 2 • Chapter 1 Apply Addition and Subtraction Concepts
Name Co
pyri
ght
© T
he M
cGra
w-H
ill C
ompa
nies
, Inc
. Per
mis
sion
is g
rant
ed t
o re
prod
uce
for
clas
sroo
m u
se.
Lesson 3 Reteach
Doubles and Near Doubles
Addends that are the same are called doubles.
Two addends that are almost doubles are near
doubles.
3 + 3 = 6
Add. Use doubles.
3 + 4 = 7
1. 4 + 4 = 8
2. 6 + 5 =
3. 2 + 3 =
4. 5 + 5 =
addend addend
Grade 2 • Chapter 1 Apply Addition and Subtraction Concepts 5
Name Copyright ©
The McG
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ill Companies, Inc. Perm
ission is granted to reproduce for classroom use.
Lesson 4 Reteach
Make a 10
You can make a 10 to find 8 + 3:
1. Add to 8 to make 10.
2. Subtract the same number from 3.
3. Add the sum and difference.
4. The answer is also the sum of 8 + 3.
We know that 10 + 1 equals 11, so 8 + 3 also equals 11. 10 + 1 = 11 and 8 + 3 = 11
Make a 10 to add. Use the example above for help.
8 + 3 = ?
10 + 1 = 11
8 + 2 = 10 3 - 2 = 1
1.
9 + 5 = ?
+ =
9 + = 10 5 - =
So, 9 + 5 = .
2.
7 + 6 = ?
+ =
7 + = 10 6 - =
So, 7 + 6 = .
6 Grade 2 • Chapter 1 Apply Addition and Subtraction Concepts
Name Co
pyri
ght
© T
he M
cGra
w-H
ill C
ompa
nies
, Inc
. Per
mis
sion
is g
rant
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o re
prod
uce
for
clas
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se.
Lesson 5 Reteach
Add Three Numbers
You can group addends. Find a double. Make a 10.
4 6
3 8 5 10
+ 4 + 3 + 4 + 5
11 15
You can use doubles or
make a 10.
Find a double. Circle addends that make
doubles. Add.
1. 3 4 4 3 5 3 6 2 4 5 8 7
+
6 5 10
+ 7 + 7 + 2 + 4 + 4 + 5 + 3 7 + 2 + 2
13
Make a 10. Circle addends that make a 10. Add.
2. 8 2 10 + 4 + 4
14
Find the sum.
3. 8 8 9 2 8 3 3 9 8 9 18 7 7 0 0 + 8 16 + 1 10 + 2 + 2 + 8 10 + 8 16
+ + + +
4 3 10 + 6 + 3
1 9 10+ 4 + 4
8 7 8+ 3 + 10
5 6 10+ 5 + 6
Grade 2 • Chapter 1 Apply Addition and Subtraction Concepts 7
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The McG
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ission is granted to reproduce for classroom use.
Lesson 6 Reteach (1)
Problem Solving STRATEGY: Write a Number Sentence
Sanders’ Orchard sells bags of
apples. Malia buys 4 bags. Steve
buys 2 bags. How many bags of
apples do they buy in all?
What do I know?
Malia buys 4 bags. Steve buys 2 bags.
What do I need to find?
The total number of bags of apples Steve and Malia buy?
Understand
Step 1
Plan
Step 2
Solve
Step 3 Write a number sentence.
4 + 2 = 6
bags of apples
How will I solve?
I will write a number sentence.
Is my answer reasonable?
Step 4
Check
8 Grade 2 • Chapter 1 Apply Addition and Subtraction Concepts
Name Co
pyri
ght
© T
he M
cGra
w-H
ill C
ompa
nies
, Inc
. Per
mis
sion
is g
rant
ed t
o re
prod
uce
for
clas
sroo
m u
se.
Lesson 6 Reteach (2)
Problem Solving STRATEGY: Write a Number Sentence
Write a number sentence to solve.
1. A.J., Seth, and Lily each have 1 box of pencils. There are 5 pencils in each box. How many pencils do they have in all? pencils
+ + =
2. Johnny buys 3 bottles of juice for a party. He decides to buy 6 more bottles. How many total bottles does Johnny buy? bottles
+ =
3. Steffan has 3 sunflowers and 5 tulips in his garden. How many flowers are there in all? flowers
+ =
4. Mateo saw 3 red tricycles and 3 blue tricycles coming down the sidewalk. How many tricycles did he see in all? tricycles
+ =
stickers
5. Aiden has 7 robot stickers and 5 alien stickers on his folder. How many stickers in all?
+ =
Grade 2 • Chapter 1 Apply Addition and Subtraction Concepts 9
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ill Companies, Inc. Perm
ission is granted to reproduce for classroom use.
Lesson 7 Reteach
Count Back to Subtract
Count back to subtract.
8 - 2 =
6
Count back to subtract.
10 - 1 =
9
1.
7 - 4 =
3
Count back to subtract. Show how you use
to help.
2.
9 - 3 =
6
3.
9 - 2 =
7
4.
5 - 1 =
5.
6 - 2 =
6.
9 - 1 =
7.
8 - 6 =
8.
4 - 3 =
9.
7 - 3 =
10 Grade 2 • Chapter 1 Apply Addition and Subtraction Concepts
Name Co
pyri
ght
© T
he M
cGra
w-H
ill C
ompa
nies
, Inc
. Per
mis
sion
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Lesson 8 Reteach
Subtract All and Subtract Zero
5 - 0 =
5 5 - 5 =
0
Subtract 0. Subtract all.You have the same number left. You have 0 left.
Subtract. You can cross out pictures to help.
1. 2.
9 - 0 =
9 6 - 0 =
9 - 9 =
0 6 - 6 =
3. 4.
4 - 0 = 7 - 0 =
4 - 4 = 7 - 7 =
5. 6.
8 - 0 =
5 - 0 =
8 - 8 =
5 - 5 =
Grade 2 • Chapter 1 Apply Addition and Subtraction Concepts 11
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raw-H
ill Companies, Inc. Perm
ission is granted to reproduce for classroom use.
Lesson 9 Reteach
Use Doubles to Subtract
You can use doubles facts to subtract.
Remember, doubles are addends that are the same number.
If you know 6 + 6 = 12, you know 12 - 6 = 6 .
Subtract. Use doubles facts to help.
1.
4 + 4 = 8 , so
8 - 4 = .
2.
7 + 7 = , so
14 - 7 = .
3.
3 + 3 = , so
6 - 3 = .
4.
5 + 5 = , so
10 - 5 = .
5. 8 + 8 = , so
16 - 8 = .
6. 9 + 9 = , so
18 - 9 = .12 Grade 2 • Chapter 1 Apply Addition and Subtraction Concepts
Name Co
pyri
ght
© T
he M
cGra
w-H
ill C
ompa
nies
, Inc
. Per
mis
sion
is g
rant
ed t
o re
prod
uce
for
clas
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Lesson 10 Reteach
Relate Addition and Subtraction
8 + 4 = 12 These addition and subtraction facts have the same three numbers.
12 - 4 = 8
Use addition facts to subtract.
1. 2.
4 + 7 = 11 3 + 6 =
11 - 7 = 4 9 - 3 =
3. 4.
9 + 3 = 2 + 5 =
12 - 3 = 7 - 5 =
5. 6 .
2 + 8 = 1 + 6 =
10 - 2 = 7 - 6 =
Grade 2 • Chapter 1 Apply Addition and Subtraction Concepts 13
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ill Companies, Inc. Perm
ission is granted to reproduce for classroom use.
Lesson 11 Reteach
Missing Addends
9 + = 14 Write a related fact.
Related facts use the 14 - 9 = 5same numbers. So, 9 + 5 = 14.
Find the missing addend. Draw pictures to help.
1. 8 + 4 = 12
12 - 8 = 4
2. 7 + = 12
12 - 7 =
3. 5 + = 13
13 - 5 =
4. 9 + = 17
17 - 9 = 14 Grade 2 • Chapter 1 Apply Addition and Subtraction Concepts
Name Co
pyri
ght
© T
he M
cGra
w-H
ill C
ompa
nies
, Inc
. Per
mis
sion
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Lesson 12 Reteach
Fact Families
Some fact families have two addition facts and two subtraction facts.
9 + 7 = 16 16 - 7 = 9
7 + 9 = 16 16 - 9 = 7
Some fact families have one addition fact and one subtraction fact.
8 + 8 = 16 16 - 8 = 8
Complete each fact family.
1. 9 + 4 = 13 13 - 9 = 4
4 + 9 = 13 13 - 4 = 9
2. 6 + 5 = 11 - 5 =
5 + 6 = 11 - 6 =
3. 9 + 8 = 17 - 9 =
8 + 9 = 17 - 8 =
4. 7 + 7 = 14 - 7 =
Grade 2 • Chapter 1 Apply Addition and Subtraction Concepts 15
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ill Companies, Inc. Perm
ission is granted to reproduce for classroom use.
Lesson 13 Reteach
Two-Step World Problems
You can draw a model to help solve two-step
word problems.
Mia had 3 friends over for a party. 2 more friends came. Then 3 more friends came late. How many friends are over now?
Step 1 Step 2
3 friends were over
2 more came
3 + 2 = 5 friends
5 friends are over
3 more friends came late
5 + 3 = 8 friends
On a separate sheet of paper, draw a model to
help solve. Then, write the number sentences.
1. Ella found 2 pens in her room. She found 4 more pens in the kitchen. Ella then found 2 more pens in her brother’s room. How many pens did Ella find in all?
Step 1: + = Step 2: + = pens
2. Ryan saw 8 birds in a tree. 2 flew away. Ryan went outside, and 3 more birds flew away. How many birds are left?
Step 1: - = Step 2: - = pens
16 Grade 2 • Chapter 1 Apply Addition and Subtraction Concepts