# Lesson 16

Posing Percentage Problems

### Lesson Narrative

In this culminating lesson on percentages, students work in groups to collect news clippings that mention percentages and sort them according to whether they are about percent increase or percent decrease, formulate questions about them, and then share their questions with other groups in a gallery walk. The purpose for students to apply percentages in a real-world context (MP4).

### Learning Goals

Teacher Facing

• Generate questions (orally and in writing) about a real-world situation involving percent increase or decrease.
• Solve a problem about a real-world situation involving percent increase or decrease and present the solution method (in writing and through other representations).

### Student Facing

Let's explore how percentages are used in the news.

### Required Preparation

If possible, have students cut several clippings from newspapers or print advertisements that include percentages or bring in similar items from internet searches. If not possible, bring several examples yourself. Examples include coupons, news stories, and advertisements claiming an increase in product size ("Now with 33% more soap!"). Every group of 3–4 students should have a set including a variety of contexts as well as some that show a percentage increase of an amount and some that include a percentage decrease in an amount.

In the final activity, each group of 3–4 students create a visual display to be used in a gallery walk based on one of the situations. Provide materials to create these displays. During the gallery walk, students will leave feedback for each group on a sticky note they can attach to the displays. Provide several sticky notes for each group.

### Student Facing

• I can write and solve problems about real-world situations that involve percent increase and decrease.