standard_description: Determine the unknown whole number in an addition or subtraction equation relating to three whole numbers. For example, determine the unknown number that makes the equation true in each of the equations 8 + ? = 11, 5 = �� – 3, 6 + 6 = ��.
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: no