Adding and Subtracting Within 20

Name: Adding and Subtracting Within 20
Author: Insta~Lesson

1st Grade · Math · 15 min· Ccss 1.oa.c.6

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I can add and subtract within 20 using different strategies.

1
The commutative property states that in addition, numbers can be switched around and the answer will still be the same.
2
In the math mountain example, the total is at the top, and the partners or addends are at the bottom.
3
When adding more than two numbers, it can be helpful to make groups of doubles or tens to simplify the problem.

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