standard_description: Subtract multiples of 10 in the range 10-90 from multiples of 10 in the range 10-90 (positive or zero differences), using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used.
problem_activity: Stage 6: Shapes on the Coordinate Grid
Required Preparation
Materials to Copy
Blackline Masters
Which One Stage 6 Gameboard

Narrative
One partner chooses a rectangle on the coordinate plane from the board. The other partner asks questions to figure out which rectangle on the coordinate plane their partner chose.


aligns: no