### Lesson Summary

### Overview

In this *Cyberchase* activity, the students examine a rate versus time graph showing Harry's level of fitness with and without the heavy equipment needed for firefighting. They learn to fill in missing values in order to keep a constant rate. They also learn to distinguish graphs of rate versus time and graphs of quantity versus time.

### Why is this an important concept?

Students are introduced to rate in the context of exercise. This activity carefully distinguishes a graph of time versus number of steps per minute from a graph of time versus number of steps.

### Grade Level:

4-8

### Suggested Time

1 hour

### Media Resources

Firefighter Training QuickTime Video

### Materials

Handout: Rates and Graphs

Assessment: Level A

Assessment: Level B

Answer Key

### The Lesson

### Part I: Learning Activity

1. Read the following to your students: Harry wants to become a firefighter. He trains on a stair climber which keeps track of his number of steps per minute. As you watch the video clip, look for ways in which Harry keeps track of his rate. Remember that rate is the number of steps per minute.

2. Play the Firefighter Training QuickTime Video.

3. Distribute the Handout: Rates and Graphs.

4. Ask the students to complete the handout.

5. Discuss the handout responses. Note: Question 7 is very important because on the (time) versus (number of steps) graph, rate is represented by the slope of the graph, so a constant rate is a straight line. However, in the (time) versus (number of steps per minute) graph, rate is represented by the y value itself, so that a constant rate is a flat line. Be sure students understand the difference.

### Part II: Assessment

Assessment: Level A (proficiency): Students complete tables of values to find missing values that keep the rate constant.

Assessment: Level B (above proficiency): Students make a distance versus time graph and answer questions about rates.

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