Ohio Virtual Tour: Landfill
Cover It Up and Keep It Green

Overview
Students have looked at creating a landfill in the previous lessons. In this lesson they have to “cap” it. They first determine how many times they need to pass the grass seeder over their fill. The second part asks them to determine how many sprinkling systems they need to keep the grass green.

Outcome
Students will understand how to calculate the area of rectangles and circles.

Standards Addressed — Mathematics

Grade 4
Measurement Units, Benchmark A
03. Identify and select appropriate units to measure the following:

perimeter — string or links (inches or centimeters)
area — tiles (square inches or square centimeters)
volume — cubes (cubic inches or cubic centimeters)

Grade 6
Use Measurement Techniques and Tools, Benchmark C
02. Use strategies to develop formulas for finding circumference and area of circles, and to determine the area of sectors.

03. Estimate perimeter or circumference and area for circles, triangles and quadrilaterals, and surface area and volume for prisms and cylinders by estimating lengths using string or links, areas using tiles or grid and volumes using cubes.

Materials

• Graph paper (two sheets per student)

• Compass

• Tape measures or string

• Scissors

• Landfill design from the previous lesson (area and perimeter)

• Cover It Up student handout

• Keep It Green student handout (for Grade 6)

Procedure

1. Students will need the landfill designs from the previous lesson.

2. Distribute the Cover It Up student handout.

3. Review the handout, discuss the task and discuss how the task can be accomplished.

4. When students finish, have them share their findings.

5. Sixth grade students can review parts of a circle and vocabulary associated with circles including circumference, diameter, radius and sector. They should review the amount of degrees in 1⁄4 circle, 1⁄2 circle and 2⁄3 circle.

6. Distribute the Keep It Green handout and discuss the task.

7. Review the relationship between the diameter of a circle and its circumference. (The circumference is about three times the diameter.)

Evaluation

Cover It Up

Keep It Green