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Fluent adding and subtracting within 20

Mathematics · Addition & Subtraction · procedural

Fluently add and subtract within 20 using mental strategies; know from memory all sums of two one-digit numbers

What mastery looks like

  • Answer any single-digit addition fact within 3 seconds
  • Recall subtraction facts within 20 from memory (e.g. 15 − 8 = 7)
  • Use known addition facts to derive related subtraction facts rapidly

Check your understanding

Can Fluent adding and subtracting within 20 instantly recall all the single-digit addition facts — like '7 + 8 = 15' — without needing to count or think for more than a second?