standard_description: Understand that rational expressions form a system analogous to the rational numbers, closed under addition, subtraction, multiplication, and division by a nonzero rational expression; add, subtract, multiply, and divide rational expressions.
problem_activity: Stage 1: Objects
Required Preparation
Materials to Gather
Connecting cubes
Materials to Copy
Blackline Masters
Number Mat 1–5

Narrative
One partner builds a tower with 5–10 cubes. The other partner rolls a cube onto the number mat to figure out how many cubes to subtract. Students work together to figure out how many cubes are left.


aligns: no