## Chapter 2

### Part 1: For activity in Teacher's Edition, page 26

Students can practice their research skills by finding facts about a roller coaster that is near you. You can also provide them with the data sheet with information about Roller Coasters found on the Activity page (PDF file).

#### Roller Coasters

Coaster |
Length |
Height |
Speed |
Duration |
Operating Since |

A | 5320 ft. | 200 ft. | 73 mi/h | 1 min 30 sec | 5/13/2000 |

B | 2260 ft. | 109 ft. 3 in. | 49.7 min | 1 min 36 sec | 5/20/1995 |

C | 3340 ft. | 115 ft. | 50 mi/h | 2 min 10 sec | 6/16/2001 |

If you use the data that we have provided, ask the students to decide what they want to put on the roller coaster bulletin board.

If students have looked up their own data, have them share what they have found and then decide what they want to put on the roller coaster bulletin board.

### Part 2: Be an Investigator

A good time to do this investigation is after Lesson 3 on addition and subtraction of whole numbers.

#### Introducing the Investigation

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

Put students in groups of two to four students to work on the investigation. Provide students with the Description of Investigation and Student Report (PDF file).

#### Doing the Investigation

Make sure the students are using subtraction to calculate the differences between the two roller coasters.

#### Wooden and Steel Roller Coasters

Name |
Lift Height |
Vertical Drop |
Speed |
Cost |
Year Constructed |

Gemini (wooden roller coaster) | 125 ft 4 in. | 118 ft | 60 mi/h | $3.4 million | 1978 |

The Top Thrill Dragster (steel roller coaster) | 420 ft | 400 ft | 120 mi/h | $25 million | 2003 |

Look for the following information in the articles the students write. Allow the students to use rounded numbers for the lift height and the cost of the Gemini.

- The Top Thrill Dragster has a lift height that is about 295 feet higher than the Gemini.
- The Top Thrill Dragster has a vertical drop that is 282 feet more than the Gemini.
- The Top Thrill Dragster goes 60 mi/h faster than the Gemini.
- The Top Thrill Dragster cost about $22 million more than the Gemini.
- The Top Thrill Dragster was constructed 25 years after the Gemini.

#### Student Report

The letter back to Robert Ortiz gives students an opportunity to write about what they have done, thus communicating about mathematics.

#### Extending the Investigation

Have students research a wooden roller coaster and a steel roller coaster near where they live and write an article about the two roller coasters, emphasizing the differences between them.