## Chapter 8

### Part 1: For the problem in the Teacher's Edition, page 184

Students can practice their research skills by finding information about canoes. Or you can provide them with the Data Sheet that shows the measurement and price of some canoes found on the Activity page (PDF file).

Display the canoe ads in your classroom.

### Part 2: Be an Investigator

A good time to do this investigation is after Lesson 7 on perimeter and area of rectangles and squares.

#### Introducing the Investigation

Introduce the investigation by reading aloud the assignment at the top of the first page of the Description of Investigation and Student Report (PDF file), by having one of your students read aloud the assignment, or by having the students read the assignment individually.

Put students in groups of two to four to work on the investigation.

#### Doing the Investigation

Help students find a strategy for solving this problem. Since the area of a rectangle is the length multiplied by the width, students could take half of the perimeter or 60 feet and split it up into two parts in different ways, for example, 10 feet and 50 feet. They can think of 10 feet as the width of the pool and 50 feet as the length of the pool. The area of that pool will be 10 × 50 or 500 square feet. Trying out different combinations of length and width, they should see that they get the maximum area for a square that is 30 feet by 30 feet.

#### Student Report

Students explain how they figured out the dimensions of the pool in the letter back to Anita Campbell. This activity gives them an important opportunity to communicate about mathematics.

#### Extending the Investigation

Have students experiment with other perimeters and see if the square always gives the maximum area.