standard_description: Derive the formula A = 1/2 ab sin(C) for the area of a triangle by drawing an auxiliary line from a vertex perpendicular to the opposite side.
problem_activity: Stage 1: Grade K Shapes
Required Preparation
Materials to Gather
Counters
Materials to Copy
Blackline Masters
Which One Stage 1 Gameboard

Narrative
One partner chooses a shape on the gameboard. The other partner asks questions to figure out what shape they chose. Students may use counters to cover up shapes that have been eliminated. Students work with simple shapes such as circles, rectangles, and triangles.


aligns: no