## Chapter 12

### Part 1: For the activity in the Teacher's Edition, page 328

Provide students with a copy of the Activity Page (PDF file).

Lesson 4 in this chapter is on elapsed time. You may want to wait to assign this activity until after students have completed Lesson 4. If the school schedule varies from day to day, you might want to put students in groups, with each group taking a different day of the week.

Answers will vary.

### Part 2: Be an Investigator

A good time to do this investigation is after Lesson 7 on temperature.

### Materials

- thermometer

#### 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

Decide with your students on a good time each day to take the temperature outside.

If you do not want to take the temperature each day, you could take the high temperature reported by your local newspaper each day. Or you could use the following table recorded from a week in San Francisco in June.

Day | Temperature |
---|---|

1 | 75°F |

2 | 77°F |

3 | 80°F |

4 | 81°F |

5 | 83°F |

When students have completed the table, created a bar graph, and answered the questions, ask them how they found their answers. Students can subtract the lower temperature from the higher to find the difference or they look at their bar graphs.

#### Answers:

Answers will vary if students collect their own data.

Answers if you use the data we provided:

**Which two days in a row had the greatest difference in temperature?**The greatest difference in temperature was 3 degrees Fahrenheit between Day 2 and Day 3.**Which two days in a row had the least difference in temperature?**The least difference in temperature was 1 degree Fahrenheit between Day 3 and Day 4.**Did the temperature always increase (or decrease) from day to day or did it go up and down?**The temperature increased each day in this five-day period.

#### Student Report

The Student Report gives students an opportunity to show and explain what they have done.

#### Extending the Investigation

Keep track of the temperature in another location in the world via the Internet for five days. Have the students record the highest temperature for each of the five days in a table. Look at the data and answer the same questions asked in the investigation.