Grade 2 · Operations and Algebraic Thinking

CCSS.MATH.CONTENT.2.OA.B.2

Fluently add and subtract within 20 using mental strategies. By end of Grade 2, know from memory all sums of two one-digit numbers.

Read this standard on the official Common Core site

Lessons that teach this standard

• Addition and Subtraction Strategies Within 20

  Add and subtract within 20 in your head: count on, turn a sum around, make a ten, use doubles, subtract through ten, and use a fact you know. Grades 1–2.