Addition and Subtraction Math Strategies A set of 11 math posters By Laura Zindle
[email protected] [email protected] Graphics from www.scrappindoodles.com ©2011 Laura Zindle
Addition Strategies included… Zero Strategy One More and Two More Strategy Commutative Strategy Sums of 10 Doubles Strategy Near Doubles Strategy Make a Ten Ten Plus
Subtraction Strategies included… Think Addition Build Up Through 10 Back Down Through 10 Note: Back Down Through 10 is a 2 page poster that will need to be pasted together while trimming off the added border.
Zero Strategy When one addend is 0 Example: 6 + 0 = 6
One More and Two More Strategy Count on 1 more or 2 more Example 5 + 2 = 7
1
2
3
4
5
6
7
Commutative Strategy The order of the addends does not affect the sum Example: 7 + 3 = 10 and 3 + 7 = 10 +
+
=
=
Sums of Ten Any two numbers that add up to ten Example: 8 + 2 = 10
=
+
8
2
10
Doubles Strategy When two addends are the same Example: 4 + 4 = 8
Add 4 More
Near Doubles Strategy When one addend is one more than the other Example: 5 + 5 = 10 so 5 + 6 = 11
Add 5 More
Add 1 More
Make a Ten Make ten by subtracting the required amount from one addend and adding it on to the other addend Example: 9 + 3 can become 10 + 2
Add 1 Add 2 More
Ten Plus When one addend is 10 Example: 10 + 4 = 14
10
Add More
Think Addition When an addition fact helps solve the subtraction fact. Example: 5 + 5 = 10 so, 10 – 5 = 5 5 + 5 = 10
Think Addition
10 – 5 = 5
Build up Through 10 This is used for subtraction facts that have a number minus 8 or 9. Instead of subtracting, you build up starting with the 8 or the 9. Example: 14 – 8, you need 2 more to make 10, then you need 4 more to get 14. So, 14 – 8 is 2 + 4, which is 6.
Start with 8
Add 2 More
Add 4 More
Back Down Through 10 This is used for facts where one of the digits is close to the number being subtracted. Example: 15 – 6, take away 5 to get to 10, and then one more to get to 9
Start with 15
Take away 5 to get 10
Then 1 more to get 9