Show:
estimate
quick mental math
regrouping
properties
friendly numbers & partial sums
100

Round both addends to the nearest 10 and estimate.

32 + 27

30 + 30 =

about 60

100

10 more than 6

16

100

Draw 16 ones in base ten block. Can you regroup and make a ten? Draw it out. 

1 ten and 6 ones

100

5 + 3 = 8 

3 + 5 = 8

Name the addition property. 

Commutative Property of Addition

The order of the addends does not change the sum. 

100

Make a friendly number with . . . 

47 + 99

47 + 99

-1        +1

46 + 100

200

Round both addends to the nearest 10 and estimate.

72 + 25

70 + 30 = 

about 100
200

100 more than 34

134

200

Show your answer in base ten blocks. Show how you regrouped.


14 + 26 = ___

drawing should show 4 tens

the sum is 40

200

64 + 0 = 64

Name the addition property. 

Identity Property of Addition

The sum of any number and zero is that number. 

200

Solve using partial sums.

  79 =   70 + ___

+54 =   50 + ___

  79 =   70 +  9

+54 =   50 +  4


= 133

300

Round both addends to the nearest 100 and estimate.

123 + 580

100 + 600 =

about 700

300

two hundred more than 158

358

300

Show your answer in base ten blocks. Show how you regrouped. 

148 + 53 = ___

drawing should show 2 hundreds and 1 one. 

the sum is 201

300

15 + (12 + 3) = 30

Name the addition property. 

Associative Property of Addition

The way the addends are grouped does not change the sum. 

300

Solve by making a friendly number. 

39 + 36 = ___

39 + 36

  +1      -1

40 + 35 = 75

400

Round both addends to the nearest 100 and estimate.

89 + 71

100 + 100 = 
about 200
400

32 + 200

232

400

Show your answer in base ten blocks. Show how you regrouped. 

138 + 171 = ___

drawing should show 3 hundreds and 9 ones.

the sum is 309

400

(8 + 12) + 7 = ____

8 + (12 + 7) = ____

SOLVE and name the addition property. 

the sum is 27

Associative Property of Addition.

400

Solve by using partial sums.

  325 = ___ + ___ + ___

+625 = ___ + ___ + ___

  325 = 300 + 20 + 5

+625 = 600 + 20 + 5


the sum is 950


500

Round both addends to the nearest 100 and estimate.

2,613 + 3,177

2,600 + 3,200 =

about 5,800

500

1,000 more than 4,529

5,529

500

Show your answer in base ten blocks. Show how you regrouped. 

632 + 454 = ___

1 thousand, 8 tens, 6 ones

the sum is 1,086

500

24 + ___ = 36

___ + 24 = 35

SOLVE and name the addition property.

24 + 12 = 36

Commutative Property

500

Solve by making a friendly number.

598 + 256 = ___

598 + 256

   +2          -2

600 + 254 = 854