Lesson 4

How Do We Choose?

Lesson Narrative

This lesson is optional. This is the first of three lessons that explore the mathematics of voting: democratic processes for making decisions. The activities in these lesson build on each other. Doing all of the activities in the three lessons would take more than three class periods—possibly as many as five. It is not necessary to do the entire set of activities to get some benefit from them, although more connections are made the farther one gets. As with all lessons in this unit, all related standards have been addressed in prior units; this lesson provides an optional opportunity to go more deeply and make connections between concepts.

The activities in this lesson are about voting on issues where there are two choices. Students use equivalent ratio concepts and skills developed in grade 6 to compare voting results of two groups, to determine whether an issue wins an election with a supermajority rule, and discover that a few people can determine the results of an election when very few people vote.

Most of the activities use students’ skills from earlier units to reason about ratios (MP2) in the context of real-world problems (MP4). While some of the activities do not involve much computation, they all require serious thinking. In many activities, students have to make choices about how to assign votes and justify their methods (MP3).

Most importantly, this lesson addresses topics that are important for citizens in a democracy to understand. Teachers may wish to collaborate with a civics or government teacher to learn how the fictional middle-school situations in this lesson relate to real-world elections.

Learning Goals

Teacher Facing

  • Apply reasoning about ratios and percentages to analyze (orally and in writing) voting situations involving two choices.
  • Comprehend the terms “majority” and “supermajority” (in spoken and written language).
  • Critique (using words and other representations) a statement reporting the results of a vote.

Student Facing

Let's vote and choose a winner!

CCSS Standards