# CCSS.1.OA.C.6

addition facts, subtraction facts, within 20; calculate, fluently compute, explain.

System: US Common Core Math
Route: /math/standards/us-ccss/curratom-us-ccss-1-oa-c-6
Skills: 4

## Skills and Examples

- [Add Within 10 Concrete](/math/skills/oa/add-within-10-concrete) — Whole-Number Operations and Fact Fluency
- [Add Within 20 Strategies](/math/skills/oa/add-within-20-strategies) — Whole-Number Operations and Fact Fluency
- [Sub Within 10 Concrete](/math/skills/oa/sub-within-10-concrete) — Whole-Number Operations and Fact Fluency
- [Sub Within 20 Strategies](/math/skills/oa/sub-within-20-strategies) — Whole-Number Operations and Fact Fluency