Week 11: Subtraction up to 20

Skills and concepts for Subtraction up to 20.

1. 1. Subtraction Sentences Using Number Lines - Up to 20
2. 2. Subtract by Counting Back - Up to 20
3. 3. Subtracting 1
4. 4. Subtracting 2
5. 5. Subtracting 3
6. 6. Subtracting 4