1.OA.3:
Operations And Algebraic Thinking
Understand And Apply Properties Of Operations And The Relationship Between Addition And Subtraction.
Apply properties of operations as strategies to add and subtract.3 Examples: If 8 + 3 = 11 is known, then 3 + 8 = 11 is also known. (Commutative property of addition.) To add 2 + 6 + 4, the second two numbers can be added to make a ten, so 2 + 6 + 4 = 2 + 10 = 12. (Associative property of addition.)
1.OA.5:
Operations And Algebraic Thinking
Add And Subtract Within 20.
Relate counting to addition and subtraction (e.g., by counting on 2 to add 2).