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TRANSCRIPT
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Table of Contents click on the topic to go to that section
- Subtracting Ten on a Number Grid- Subtracting Ten Patterns
- Patterns When Subtracting Multiples of Ten
- Two Digit Minus One Digit
- Subtracting Ten from Multiples of Ten in Our Head
- Two Digit Minus Two Digit- Two Digit Minus Two Digit Pt. 2
- Word Problems
- Subtracting Ten from Multiples of Ten with Blocks
- Subtracting Multiples of Ten with Blocks
- Subtracting Ten with Blocks
- Subtracting Multiples of Ten on a Number Grid
- Extra Word Problems (If needed)
- Lab: Subtraction Dice Roll
- Lab: Subtraction Spin
- Lab: Subtraction Around the Room
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Standards for Mathematical Practices
MP 8 Look for and express regularity in repeated reasoning.
MP 1 Make sense of problems and persevere in solving them.
MP 2 Reason abstractly and quantitatively.
MP 3 Construct viable arguments and critique the reasoning of others.
MP 4 Model with mathematics.
MP 5 Use appropriate tools strategically.
MP 6 Attend to precision.
MP 7 Look for and make use of structure.
Click on each standard to bring you to an example of how to meet
this standard within the unit.
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Subtracting 10 from Multiples of 10 with Blocks
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Subtracting 10 from Multiples of 10 with Blocks
Click to return to Table of Contents
Teac
her N
otes
[This object is a teacher notes pull tab]
Students will need base ten blocks and place value charts for this lesson.
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How is subtracting 6 - 1 similar to 60 - 10?
Class Discussion
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How is subtracting 6 - 1 similar to 60 - 10?
Class Discussion
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Teac
her N
otes
Discuss how 6 cubes take away 1 cube make 5 cubes.
Then 6 longs take away 1 long make 5 longs. They
both have the same amount of blocks but the blocks are
worth different values.
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1 The base ten blocks show 20 - 10 = 10
True
False
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1 The base ten blocks show 20 - 10 = 10
True
False
[This object is a pull tab]
Ans
wer
False
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2 60 - 10 = ______
A 5
B 50
C 70
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2 60 - 10 = ______
A 5
B 50
C 70
[This object is a pull tab]
Ans
wer
A
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3 8 tens - 1 ten = ______ tens
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3 8 tens - 1 ten = ______ tens
[This object is a pull tab]
Ans
wer
7
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4 Which block should we use to show
50 - 10 = ______
A 40
B cube
C long
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4 Which block should we use to show
50 - 10 = ______
A 40
B cube
C long[This object is a pull tab]
Ans
wer
C
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Subtracting Ten From Multiples of Ten in Our Heads
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10 20 30 40 50
60 70 80 90 100
100, ____, ____, ____, ____, ____, ____, ____, ____, ____
Let's Count By Tens
Now let's write them backwards starting with 100!
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10 20 30 40 50
60 70 80 90 100
100, ____, ____, ____, ____, ____, ____, ____, ____, ____
Let's Count By Tens
Now let's write them backwards starting with 100!
[This object is a pull tab]
Teac
her N
otes Click on each long to make it
disappear and reveal the number. Take lots of time
during this lesson to practice counting backwards by 10.
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Let's Count Back By Tens. Start 100!
100 90 80 70 60
50 40 30 20 10
Now let's write them forwards starting with 10!
10, ______, ______, ______, ______,
______, ______, ______, ______, ______
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Let's Count Back By Tens. Start 100!
100 90 80 70 60
50 40 30 20 10
Now let's write them forwards starting with 10!
10, ______, ______, ______, ______,
______, ______, ______, ______, ______
Teac
her N
otes
[This object is a teacher notes pull tab]
Click on each dime to make the number appear.
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100, 90, 80, 70, 60, 50, 40, 30, 20, 10What pattern do you see
when counting backwards?
100, 90, 80, 70, 60, 50, 40, 30, 20, 10
Patterns when Counting
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100, 90, 80, 70, 60, 50, 40, 30, 20, 10What pattern do you see
when counting backwards?
100, 90, 80, 70, 60, 50, 40, 30, 20, 10
Patterns when Counting
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Teac
her N
otes
&
Mat
h Pr
actic
e
MP 7 Look for and make use of structure
Ask students to identify the pattern they see and how they
think the pattern could help them.
Click on the question to show the numbers with the pattern
highlighted.
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Practice
50, 40, 30, ______, ______
90, 80, 70, ______, ______
80, 70, 60, ______, ______
100, 90, 80, ______, ______
60, 50, 40, ______, ______
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When subtracting ten,
the tens place goes down by 1.
50 - 10 = 40
70 - 10 = 60
Subtracting
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When subtracting ten,
the tens place goes down by 1.
50 - 10 = 40
70 - 10 = 60
Subtracting
Teac
her N
otes
[This object is a teacher notes pull tab]
Discuss how 5 went down to 4 which is 1 less and how 7 went down to 6 which is one
less.
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Practice
80 - 10 = ______
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Practice
40 - 10 = ______
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60 - 10 = ______
Practice
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6 30 - 10 = ______
A 40
B 20
C 30
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6 30 - 10 = ______
A 40
B 20
C 30
[This object is a pull tab]
Ans
wer
B
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7 10 - 10 = ______
A 20
B 0
C 10
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7 10 - 10 = ______
A 20
B 0
C 10
[This object is a pull tab]
Ans
wer
B
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8 70 - 10 = ______
A 60
B 80
C 10
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8 70 - 10 = ______
A 60
B 80
C 10
[This object is a pull tab]
Ans
wer
A
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9 90 - 10 =
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9 90 - 10 =
[This object is a pull tab]
Ans
wer
80
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10 20 - 10 =
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10 20 - 10 =
[This object is a pull tab]
Ans
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10
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Subtracting 10 with Blocks
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Teac
her N
otes
[This object is a teacher notes pull tab]
Students will need base ten blocks and place value charts for this lesson.
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11 34 - 10 = 24
Yes
No
** Use blocks at your desk to help you **
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11 34 - 10 = 24
Yes
No
** Use blocks at your desk to help you **[This object is a pull tab]
Ans
wer
Yes
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15 82 - 10 = ______
** Use blocks at your desk to help you **
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15 82 - 10 = ______
** Use blocks at your desk to help you **
[This object is a pull tab]
Ans
wer
72
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Subtracting Ten on a Number Grid
Click to return to Table of Contents
Teac
her N
otes
[This object is a teacher notes pull tab]
Before starting this lesson, review
multiples of 10 with the students by
counting by 10 and listing multiples of
10 on the board. All students will need a
number grid.
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Subtracting 10 is very easy when using a number grid.Find the number you are subtracting 10 from on the number
grid and circle it. Then move up one box.
Number Grid
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24 - 10 = 14
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24 - 10 = 14
Teac
her N
otes
[This object is a teacher notes pull tab]
Discuss why 24 is circled. Allow students to count the boxes one jump at a time to confirm that one jump up is
that same as ten jumps.
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40 - 10 = 30
Find the first number on the number grid.Since we are subtracting from a multiple of 10, the
number will always be in the last row.Then, move up one jump.
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Let's try another one56 - 10 =
First, find the number on the number grid.Then jump up one.
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Let's try another one34 - 10 =
What number should we circle?
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Let's try another one63 - 10 =
What number should we circle?
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Let's try another one19 - 10 =
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Let's try another one80 - 10 =
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Class Discussion
John used his number grid to help solve the subtraction sentence below. He said the answer is
25. Is he correct? What did he do wrong?
24 - 10 =
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Class Discussion
John used his number grid to help solve the subtraction sentence below. He said the answer is
25. Is he correct? What did he do wrong?
24 - 10 =
[This object is a pull tab]
Mat
h Pr
actic
e
MP 3 Construct viable arguments and critique the
reasoning of others
In small groups give students time to voice their opinions about the problems. Then
allow a whole class discussion on why he is or is not correct.
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16 25 - 10 = 24
Yes
No
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16 25 - 10 = 24
Yes
No
[This object is a pull tab]
Ans
wer
No
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17 39 - 10 = 49
True
False
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17 39 - 10 = 49
True
False
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Ans
wer
False
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18 58 - 10 = ______
A 68
B 48
C 58
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18 58 - 10 = ______
A 68
B 48
C 58
[This object is a pull tab]
Ans
wer
B
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19 34 - 10 =
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19 34 - 10 =
[This object is a pull tab]
Ans
wer
24
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20 74 - 10 =
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20 74 - 10 =
[This object is a pull tab]
Ans
wer
64
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46- 10 36
When subtracting 10,the tens place always goes down 1 and the ones place
stays the same.
Tens
One
s
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24- 10 14
39- 10 29
77- 10 67
62- 10 52
Slide 74 (Answer) / 225
24- 10 14
39- 10 29
77- 10 67
62- 10 52
Teac
her N
otes
[This object is a teacher notes pull tab]
Discuss the pattern in the tens place.
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6 4- 1 0
5 6- 1 0
3 7- 1 0
2 3- 1 0
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Let's Practice
65 - 10 = _____
85 - 10 = _____
38 - 10 = _____
61 - 10 = _____
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Let's Practice
65 - 10 = _____
85 - 10 = _____
38 - 10 = _____
61 - 10 = _____[This object is a pull tab]
Mat
h Pr
actic
e
MP 8 Look for and express regularity in repeated reasoning
Ask students if they can find a shortcut to solve these
problems and how it would make it easier.
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Web Practice
Click here for a game. Select level 3
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21 59 - 10 = 69
True
False
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21 59 - 10 = 69
True
False
[This object is a pull tab]
Ans
wer
False
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22 67 - 10 = ______
A 57
B 77
C 66
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22 67 - 10 = ______
A 57
B 77
C 66
[This object is a pull tab]
Ans
wer
A
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23 31 - 10 = ______
A 41
B 21
C 30
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23 31 - 10 = ______
A 41
B 21
C 30
[This object is a pull tab]
Ans
wer
B
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24 45 - 10 =
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24 45 - 10 =
[This object is a pull tab]
Ans
wer
35
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25 32 - 10 =
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25 32 - 10 =
[This object is a pull tab]
Ans
wer
22
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Subtracting Multiples of 10with Blocks
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Subtracting Multiples of 10with Blocks
Click to return to Table of Contents
Teac
her N
otes
[This object is a teacher notes pull tab]
Students will need base ten blocks and place value charts for this lesson.
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26 Does 40 - 20 = 10?
Yes
No
** Use your blocks to help you **
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26 Does 40 - 20 = 10?
Yes
No
** Use your blocks to help you **
[This object is a pull tab]
Ans
wer
No
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27 80 - 70 = 10
True
False
** Use your blocks to help you **
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27 80 - 70 = 10
True
False
** Use your blocks to help you **[This object is a pull tab]
Ans
wer
True
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28 40 - 30 = ______
A 20
B 70
C 10
** Use your blocks to help you **
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28 40 - 30 = ______
A 20
B 70
C 10
** Use your blocks to help you **
[This object is a pull tab]
Ans
wer
C
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29 90 - 60 = ______
** Use your blocks to help you **
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29 90 - 60 = ______
** Use your blocks to help you **[This object is a pull tab]
Ans
wer
30
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30 50 - 50 = ______
** Use your blocks to help you **
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30 50 - 50 = ______
** Use your blocks to help you **[This object is a pull tab]
Ans
wer
0
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Subtracting Multiples of Ten on a Number Grid
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Subtracting Multiples of Ten on a Number Grid
Click to return to Table of Contents
Teac
her N
otes
[This object is a teacher notes pull tab]
Before starting this lesson, review
multiples of 10 with the students by
counting by 10 and listing multiples of 10
on the board.
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Let's warm up our brains by skip counting by 10's
using different voices.
Can you count by 10s in a:
- scary voice?
- mommy voice?
- baby voice?
- daddy voice?
10, 20, 30
Count by 10's
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To subtract multiples of 10 on a number grid, you count by 10s.
60 - 40 = ______Find the first number on the grid and circle it.
Count by 10s and move up one jump for each number you say. Stop when you say the second number in the subtraction
sentence. The number you land on is the answer.
10203040
Subtract
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Count by 10 as you move up to solve the subtraction sentence.
80 - 20 = ______What number should you circle?
Subtract
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Count by 10 as you move up to solve the subtraction sentence.
80 - 20 = ______What number should you circle?
Subtract
Teac
her N
otes
[This object is a teacher notes pull tab]
Have students work through these problems at
their seats as another student demonstrates it on the board.
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Count by 10 as you move up to solve the subtraction sentence.
30 - 10 = ______What number should you circle?
Subtract
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Count by 10 as you move up to solve the subtraction sentence.
70 - 50 = ______What number should you circle?
Subtract
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90 - 20 = ______
Subtract
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50 - 40 = ______
Subtract
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50 - 40 = ______
Subtract
[This object is a pull tab]
Mat
h Pr
actic
e
MP 5 Use appropriate tools strategically
Have students verbally explain to a partner how they
would use the grid to help them solve the problem.
Have a student then explain each step as they solve the
problem at the board.
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31 60 - 20 = ______
A 80
B 50
C 40
** Use your number grid to help you **
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31 60 - 20 = ______
A 80
B 50
C 40
** Use your number grid to help you **
[This object is a pull tab]
Ans
wer
C
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32 When subtracting multiples of 10, we need to count by ______.
A 1
B 5
C 10
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32 When subtracting multiples of 10, we need to count by ______.
A 1
B 5
C 10
[This object is a pull tab]
Ans
wer
C
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33 90 - 40 = ______
A 40
B 50
C 60
** Use your number grid to help you **
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33 90 - 40 = ______
A 40
B 50
C 60
** Use your number grid to help you **[This object is a pull tab]
Ans
wer
B
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34 50 - 30 = ______
** Use your number grid to help you **
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34 50 - 30 = ______
** Use your number grid to help you **[This object is a pull tab]
Ans
wer
20
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35 20 - 10 = ______
** Use your number grid to help you **
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35 20 - 10 = ______
** Use your number grid to help you **[This object is a pull tab]
Ans
wer
10
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Patterns When SubtractingMultiples of Ten
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Let's Count By 10s
What digit changes when we count by 10s?
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Let's Count By 10s
What digit changes when we count by 10s?
Teac
her N
otes
[This object is a teacher notes pull tab]
Write the numbers on the lines.
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What number is this?
Take 20 away and what number does it become?
What digit changed?
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What number is this?
Take 20 away and what number does it become?
What digit changed?
Teac
her N
otes
[This object is a teacher notes pull tab]
Cross out 2 longs and have the students recount.
Discuss how the tens place changed but not the ones since we subtracted 10s.
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30 - 20 = 10
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30 - 20 = 10Te
ache
r Not
es
[This object is a teacher notes pull tab]
Review how the tens place changed when we subtracted
10.
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What number is this?
What digit changed?
Take 40 away and what number does it become?
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What number is this?
What digit changed?
Take ten away and what number does it become?
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Count back by 10s
60, 50, ___, ___, ___, ___
70, 60, ___, ___, ___, ___
40, 30, ___, ___, ___, ___
60, 50, ___, ___, ___, ___
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Count back by 10s
60, 50, ___, ___, ___, ___
70, 60, ___, ___, ___, ___
40, 30, ___, ___, ___, ___
60, 50, ___, ___, ___, ___
Teac
her N
otes
[This object is a teacher notes pull tab]
Review that when counting by 10s, the tens place goes down 1 and the ones place
stays the same.
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40
206030
8070
What number is 20 less?
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36 10 less than 50 is 5?
True
False
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36 10 less than 50 is 5?
True
False
[This object is a pull tab]
Ans
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False
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37 20 less than 90 is 80?
Yes
No
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37 20 less than 90 is 80?
Yes
No
[This object is a pull tab]
Ans
wer
No
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38 What is 30 less than 40?
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38 What is 30 less than 40?
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Ans
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10
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39 What is 40 less than 50?
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39 What is 40 less than 50?
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Ans
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10
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40 70 - 40 = ?
QUIZ
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40 70 - 40 = ?
QUIZ
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Ans
wer
30
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Lab: Subtracting 10 Dice Roll
Directions:· Split students into groups of 2 and give each group 2 dice· Each student rolls 1 dice and they work together to build the largest two digit number with their dice· Students write the number in the box on their worksheet· Students subtract 10 and write the answer on the line
Click to return to Table of Contents
Click here for more information.
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When subtracting a 1 digit number from a 2 digit number, it is very important to line them up on top of
each other.
36 - 2
All of the numbers should be on the right
Subtracting
Slide 131 (Answer) / 225
When subtracting a 1 digit number from a 2 digit number, it is very important to line them up on top of
each other.
36 - 2
All of the numbers should be on the right
Subtracting
Teac
her N
otes
[This object is a teacher notes pull tab]
You may need to review digits vs numbers with the
kids prior to this lesson. In addition, review place value.
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Can you line up these numbers?
24- 4
Subtracting
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Can you line up these numbers?
58- 6
Subtracting
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Can you line up these numbers?
73- 1
Subtracting
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Can you line up these numbers?
73- 1
Subtracting
[This object is a pull tab]
Mat
h Pr
actic
e
MP 6 Attend to precision
Ask students what would happen if they don't line the
numbers up correctly.
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Once the numbers are lined up,subtract the ones first and then the tens.
2 7- 4
One
s
It may help you to draw a line between the tens and ones.
3
When there is no digit in the tens
place, we know it is a 0. 0
2It is important to line up
the answer as well!!
Subtracting
Slide 136 / 225
Remember to subtract the ones first and then the tens!!!
5 3- 1
One
s
It may help you to draw a line between the tens and ones.
When there is no digit in the tens place, we know it is a 0. 0
It is important to line up the answer as well!!
Subtracting
Slide 137 / 225
Remember to subtract the ones first and then the tens!!!
79- 8
One
s
It may help you to draw a line between the tens and ones.
It is important to line up the answer as well!!
Subtracting
Slide 138 / 225
Remember to subtract the ones first and then the tens!!!
65- 3
One
s
It may help you to draw a line between the tens and ones.
It is important to line up the answer as
well!!
Subtracting
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Remember to subtract the ones first and then the tens!!!
9 6- 5
Subtract
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Remember to subtract the ones first and then the tens!!!
3 5- 3
Subtract
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Remember to subtract the ones first and then the tens!!!
2 6- 2
Subtract
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Remember to subtract the ones first and then the tens!!!
2 6- 2
Subtract
[This object is a pull tab]
Mat
h Pr
actic
e
MP 2 Reason abstractly and quantitatively
Ask students if the answer is going to be more than or less than 26. Have them explain
their reasoning.
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Web Practice
Click here for a game. Select level 4
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41 3 9 - 7
A 32
B 31
C 36
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41 3 9 - 7
A 32
B 31
C 36 [This object is a pull tab]
Ans
wer
A
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42 1 4 - 3
A 17
B 7
C 11
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42 1 4 - 3
A 17
B 7
C 11[This object is a pull tab]
Ans
wer
C
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43 7 7 - 5
Slide 145 (Answer) / 225
43 7 7 - 5
[This object is a pull tab]
Ans
wer
72
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44 8 4 - 3
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44 8 4 - 3
[This object is a pull tab]
Ans
wer
81
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45 2 7 - 2
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45 2 7 - 2
[This object is a pull tab]
Ans
wer
25
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What number is represented below?
Two Digit Subtraction
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24
Now we want to take away 11
When we take away we always start with the bigger number.
Two Digit Subtraction
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tens ones
2 41 1-
First subtract the ones by crossing them out.
How many are left?
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Next cross out the tens
How many are left?
3
tens ones
2 41 1-
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tens ones
2 41 1-
31
Two Digit Subtraction
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What number is shown below?
Two Digit Subtraction
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47
Now we want to take away 23
Remember we always start with the bigger number.
Two Digit Subtraction
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tens ones
4 72 3-
First cross out the ones
How many are left?
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tens ones
4 72 3-
Next cross out the tens
How many are left?
4
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tens ones
4 72 3-
42
Two Digit Subtraction
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tens ones
3 4 3 1-
First cross out the ones.Next cross out the tens.What is the answer?
Subtract
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tens ones
6 8 4 7-
First cross out the ones.Next cross out the tens.What is the answer?
Subtract
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tens ones
5 2 3 2-
First cross out the ones.Next cross out the tens.What is the answer?
Subtract
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tens ones
4 9 2 7-
First cross out the ones.Next cross out the tens.What is the answer?
Subtract
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Roll the two set of dice.Place the larger number at the top of the problem.
Place the second number under the first number. Subtract.
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46 3 5 - 1 2 2 3
Yes
No
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46 3 5 - 1 2 2 3
Yes
No[This object is a pull tab]
Ans
wer
Yes
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47 6 9 - 5 6 3 3
Yes
No
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47 6 9 - 5 6 3 3
Yes
No [This object is a pull tab]
Ans
wer
No
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48 2 4 - 1 2
A 36
B 2
C 12
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48 2 4 - 1 2
A 36
B 2
C 12 [This object is a pull tab]
Ans
wer
C
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Draw base ten blocks to help you solve this problem.
49 3 6 - 2 2
A 14
B 24
C 58
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Draw base ten blocks to help you solve this problem.
49 3 6 - 2 2
A 14
B 24
C 58 [This object is a pull tab]
Ans
wer
A
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50 7 8 - 4 3
Draw base ten blocks to help you solve this problem.
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50 7 8 - 4 3
Draw base ten blocks to help you solve this problem.
[This object is a pull tab]
Ans
wer
35
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34- 23
When subtracting two digit numbers, it is important to still line up the numbers.
34- 23
Subtracting Two Digit Numbers
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34- 23
When subtracting two digit numbers, it is important to still line up the numbers.
34- 23
Subtracting Two Digit Numbers
Teac
her N
otes
[This object is a teacher notes pull tab]
Show students how the ones and tens are lined up. Also, point out where the minus
sign is. Have students practice writing the problem
on their own paper to be sure they are lining the numbers up correctly.
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3 42 3-
Once the numbers are lined up,draw a line between the tens and ones.
First subtract the ones.
Think of it as two smaller subtraction problems
One
s
Tens
Subtracting Two Digit Numbers
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3 42 3-
After you subtract the ones,subtract the tens!
One
s
Tens
11Don't forget to line up the answer too!
Subtracting Two Digit Numbers
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7 6 4 5-
Let's try one!
One
s
Tens
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7 6 4 5-
Let's try one!
One
s
Tens
Teac
her N
otes
[This object is a teacher notes pull tab]
Have the students practice lining up the numbers by pulling
the digits to the correct location. Once the numbers are lined up, have them mark the ones by either circling the ones or drawing an arrow on
top to remind them to subtract the ones first.
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3 6 5 2-
Practice
One
s
Tens
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1 46 4 -
Practice
One
s
Tens
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5 72 1-
Practice
One
s
Tens
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6 53 3-
Practice
One
s
Tens
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7 22 0-
Practice
One
s
Tens
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7 22 0-
Practice
One
s
Tens
[This object is a pull tab]
Mat
h Pr
actic
e
MP 1 Make sense of problems and persevere in solving them
Ask students how they would start this problem. Be sure that they line up the numbers. Have
them then talk out each step.
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Web Practice
Click here for a game. Select level 6
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51 6 8 - 3 6
A 94
B 32
C 31
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51 6 8 - 3 6
A 94
B 32
C 31[This object is a pull tab]
Ans
wer
B
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52 3 6 - 1 5
Slide 185 (Answer) / 225
52 3 6 - 1 5
[This object is a pull tab]
Ans
wer
21
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53 4 6 - 2 3
Slide 186 (Answer) / 225
53 4 6 - 2 3
[This object is a pull tab]
Ans
wer
13
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54 35 - 21 =
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54 35 - 21 =
[This object is a pull tab]
Ans
wer
14
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Lab: Subtraction Spin· Assemble spinners by cutting out the two circles and arrows. Attach the arrow to the center of the spinner with a brad.· Have students work with a partner.· Student 1 spins spinner A and write the number on the top line of the subtraction sentence. Repeat with spinner B and write the number under the first number.· Student 1 solves the subtraction sentence on the paper while student 2 uses a calculator to check the answer. If student 1 is incorrect, have the students work together to find the mistake.· Switch rolls and repeat.
Click to return to Table of Contents
Click here for a more information
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There are 3 different types of subtraction problems
1. Take away
2. Comparison
3. Part/Part/Whole
We solve all three by lining up the numbers on
top of each other and subtracting.
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Take Away
Take away problems ask us to find how many are left. We start with a group of objects and take some away.
There are 26 red birds on a fence and 14 fly away.
How many are left?
26 - 14 = ?
xxxxxx xxxxx xxx
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Part/Part/Whole
In part/part/whole problems,
we are looking for the missing part.
Jim has 43 Skittles.
12 of them are red.
How many are not red?
Whole
Part Part
4312 ?43 - 12 = ?
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Comparison
Comparison problems ask us to find the difference between two amounts.
How many more? How many less? How much bigger? How much smaller?
Jim has 45 pencils. Jess has 67 pencils. How many more pencils does Jess have?
67 - 45 = ?
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Sometimes subtraction word problems require multiple steps.It is helpful to underline the 2 parts in different colors.
Joe went to the store and bought 12 bananas and 21 apples. His sister ate 10 pieces of fruit. How
many apples and bananas are left?
Word Problems
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Joe went to the store and bought 12 bananas and 21 apples. His sister ate 10 pieces of fruit. How
many apples and bananas are left?
Step 1: How many pieces of fruit did Joe buy in all?
12 + 21 = ______?
In order to find how many are left, we need to first find out how many he started with.
Word Problem
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Joe went to the store and bought 12 bananas and 21 apples. His sister ate 10 pieces of fruit. How
many apples and bananas are left?
Step 1: How many pieces of fruit did Joe buy in all?
12 + 21 = ______?
In order to find how many are left, we need to first find out how many he started with.
Word Problem
Teac
her N
otes
[This object is a teacher notes pull tab]
Click on the ? to show the addition problem.
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Joe went to the store and bought 12 bananas and 21 apples. His sister ate 10 pieces of fruit. How many
apples and bananas are left?
Step 2: How many pieces are left after his sister ate some?
33 - 10 = ______?
Word Problem
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What type of problem is it?
Bob went to the grocery store. He bought 18 hot dogs and 29
hamburgers for a party. How many more hamburgers did he
buy than hot dogs?
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What type of problem is it?
Bob went to the grocery store. He bought 18 hot dogs and 29
hamburgers for a party. How many more hamburgers did he
buy than hot dogs?
Teac
her N
otes
[This object is a teacher notes pull tab]
Work through the problems with the students. Take time
to discuss what type of problem it is. Have students
work on the problems at their desks while another
student completes it on the board.
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What type of problem is it?
Mom bought 36 items at the store. 23 of the items were frozen. How
many items were not frozen?
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What type of problem is it?
Dad baked 24 cookies. Jim ate 13 of the cookies. His sister ate the rest. How many did his sister eat?
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What type of problem is it?
Billy had 16 puppies for sale. 14 of them were bought. How many are left?
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What type of problem is it?
There are 37 peanut butter cups in a bag. John ate 11 and Betty ate 14. How many are left?
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What type of problem is it?
Jess weighs 68 pounds. Her sister weighs 34 pounds. How much less
does her sister weigh?
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55 Which type of subtraction story is this?
Jen had 27 nail polishes. 12 of them broke. How many are left?
A Part/Part/Whole
B Take Away
C Comparison
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55 Which type of subtraction story is this?
Jen had 27 nail polishes. 12 of them broke. How many are left?
A Part/Part/Whole
B Take Away
C Comparison[This object is a pull tab]
Ans
wer
B
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56 Which two numbers would you add first?
The pet store has 11 gray kittens and 26 white kittens. 14 kittens were bought. How many kittens are left?
A 11
B 26
C 14
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56 Which two numbers would you add first?
The pet store has 11 gray kittens and 26 white kittens. 14 kittens were bought. How many kittens are left?
A 11
B 26
C 14
[This object is a pull tab]
Ans
wer
A and B
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57 Ron has 67 dollars. He went to the store and spent 24 dollars. How much does he have left?
A 91
B 34
C 43
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57 Ron has 67 dollars. He went to the store and spent 24 dollars. How much does he have left?
A 91
B 34
C 43[This object is a pull tab]
Ans
wer
C
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58 The computer lab has 35 computers. A class comes and uses 22 computers. How many computers are not being used?
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58 The computer lab has 35 computers. A class comes and uses 22 computers. How many computers are not being used?
[This object is a pull tab]
Ans
wer
13
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59 Bob has 57 flowers in his garden. Chris has 45 flowers in his garden. How many more flowers does Bob have?
QUIZ
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59 Bob has 57 flowers in his garden. Chris has 45 flowers in his garden. How many more flowers does Bob have?
QUIZ
[This object is a pull tab]
Ans
wer
12
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Lab: Subtraction Around the RoomDirections:
· Print out one copy of the cards and laminate them.· Cut out the cards and tape them around the room.· Students move around the room looking for the subtraction problems.· Students write and solve the subtraction sentence in the box numbered with the same number as the card.
Click to return to Table of Contents
Click here for more information
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Fruit Stand Prices
40 40 90 70 20
Use the above prices for each type of fruit to solve the following problems.
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You have 55 cents.You buy an apple.How many cents do you have left?
55- 40
Fruit Stand Prices
40 40 90 70 20
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You have 72 cents.You buy a pear.How many cents do you have left?
72- 40
Fruit Stand Prices
40 40 90 70 20
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You have 63 cents.You buy a strawberry.How many cents do you have left?
63- 20
Fruit Stand Prices
40 40 90 70 20
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You have 63 cents.You buy 2 strawberries.How many cents do you have left?
63-
Fruit Stand Prices
40 40 90 70 20
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You have 63 cents.You buy 2 strawberries.How many cents do you have left?
63-
Fruit Stand Prices
40 40 90 70 20Te
ache
r Not
es
[This object is a teacher notes pull tab]
Make sure students notice that they are buying 2
strawberries in this problem. Since it is a two step problem it is important to walk through
it with them the first time.
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You have 90 cents.You buy a pineapple.How many cents do you have left?
Fruit Stand Prices
40 40 90 70 20
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60 You have 80 cents. You buy a tomato. How many cents do you have left?
Farm Stand Prices
70 50 60 40 10
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60 You have 80 cents. You buy a tomato. How many cents do you have left?
Farm Stand Prices
70 50 60 40 10
[This object is a pull tab]
Ans
wer
30
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61 You have 70 cents. You buy a green pepper. How many cents do you have left?
Farm Stand Prices
70 50 60 40 10
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61 You have 70 cents. You buy a green pepper. How many cents do you have left?
Farm Stand Prices
70 50 60 40 10
[This object is a pull tab]
Ans
wer
30
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62 You have 70 cents. You buy a potato. How many cents do you have left?
Farm Stand Prices
70 50 60 40 10
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62 You have 70 cents. You buy a potato. How many cents do you have left?
Farm Stand Prices
70 50 60 40 10
[This object is a pull tab]
Ans
wer
0
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63 You have 90 cents. You buy an ear of corn. How many cents do you have left?
Farm Stand Prices
70 50 60 40 10
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63 You have 90 cents. You buy an ear of corn. How many cents do you have left?
Farm Stand Prices
70 50 60 40 10[This object is a pull tab]
Ans
wer
30
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64 You have 90 cents. You buy 4 carrots. How many cents do you have left?
Farm Stand Prices
70 50 60 40 10
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