# CCSS.1.NBT.C.4

addition, place value, within 100; calculate, model, explain.

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

## Skills and Examples

- [Add Two Digit No Regroup](/math/skills/nbt/add-two-digit-no-regroup) — Whole-Number Operations and Fact Fluency
- [Add Two Digit Regroup](/math/skills/nbt/add-two-digit-regroup) — Whole-Number Operations and Fact Fluency
- [Place Value Tens Ones](/math/skills/nbt/place-value-tens-ones) — Base-Ten Place Value and Whole-Number Notation
- [Sub Two Digit Regroup](/math/skills/nbt/sub-two-digit-regroup) — Whole-Number Operations and Fact Fluency