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 3: Describe and Find
Required Preparation
Materials to Gather
Geoblocks
Solid shapes

Narrative
Students describe solid shapes so their partner can identify the shape out of a set of 4–6 solid shapes.


aligns: no