# CCSS.1.OA.C.5

count, calculate, explain; counting, addition, subtraction.

System: US Common Core Math
Route: /math/standards/us-ccss/curratom-us-ccss-1-oa-c-5
Skills: 4

## Skills and Examples

- [Count Back from Number](/math/skills/count/count-back-from-number) — Counting and Cardinality Foundations
- [Count On from Number](/math/skills/count/count-on-from-number) — Counting and Cardinality Foundations
- [Add Within 20 Strategies](/math/skills/oa/add-within-20-strategies) — Whole-Number Operations and Fact Fluency
- [Sub Within 20 Strategies](/math/skills/oa/sub-within-20-strategies) — Whole-Number Operations and Fact Fluency