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 1: Lines of Symmetry
Required Preparation
Materials to Gather
Colored pencils, crayons, or markers
Materials to Copy
Blackline Masters
Centimeter Grid Paper - Standard
Centimeter Dot Paper - Standard

Narrative
Each student chooses whether to use dot or grid paper. Each student creates a half of a design and draws a line of symmetry. Students switch paper and complete each other’s designs.


aligns: no