Task# Stuffing Envelopes

Illustrative MathematicsVaries

Students learn about proportional relationships and explore them through tables, graphs, and equations in 6th and 7th grade. A proportional relationship can be thought of as a linear relationship whose graph goes through the origin. Students make the step from proportional relationships in particular to linear functions in general in 8th grade. As part of this transition, students should recognize the slope of a line through the origin as the unit rate for that proportional relationship.