standard_description: Fluently add and subtract within 20 using mental strategies. (See standard 1.OA.6 for a list of mental strategies.) By end of Grade 2, know from memory all sums of two one-digit numbers.
problem_activity: Stage 4: Subtract within 20
Required Preparation
Materials to Gather
Colored pencils or crayons
Number cards 0–10
Paper clips
Materials to Copy
Blackline Masters
Capture Squares Stage 4 Gameboard
Capture Squares Stage 4 Spinner

Narrative
Students spin to get a number (16–20) and flip a card (0–10). They subtract the number on the card from the number on the spinner. The spinner includes a wild space where students can choose their own number.


aligns: yes