Common Core
K.OA.A.4
3 lessons teach this standard. Every lesson is interactive, and every one prints as a worksheet with a separate answer key.
Kindergarten Math · Chapter 4 · Lesson 3
You know the whole and one part. Find the other.
Kindergarten Math · Chapter 5 · Lesson 1
The most useful pairs there are.
Kindergarten Math · Chapter 5 · Lesson 3
Writing the ten pairs down.