Help with Opening PDF Files

## Chapter 5

### Part 1: For the problem in the Teacher's Edition, page 106

Students can practice their research skills by finding examples of timelines. Or you can provide them with the Data Sheet that shows a timeline of important events in the United States Space Program found on the Activity page (PDF file).

Look at an example of a timeline with your students and discuss how a timeline compares to the axis on a graph. On a timeline, a set amount of space represents, a certain number of years. On a graph a set amount of space can also represent a number. It may be a number of years, people, degrees, etc.

Have students create a timeline for the data of page 106.

### Part 2: Be an Investigator

A good time to do this investigation is after Lesson 6 on subtracting greater numbers.

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#### Introducing the Investigation

Introduce the investigation by reading aloud the letter at the top of 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.

If you and the students want to do a timeline on an important series of events where you live, brainstorm some ideas of what the timeline might be about. Then have students research the series of events. Or you can provide students with the information about the Statue of Liberty, using the Data Sheet found on the second page of the Description of Investigation and Student Report (PDF file).

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

#### Doing the Investigation

Make sure that students understand that the time between events on a timeline is an estimate. For example, one event might happen early in a year and the next event might happen late in another year. Remind students to pay attention to the number of years between dates and place them accordingly on the timeline.

#### Information for Statue of Liberty Timeline:

 Statue of Liberty 1876: Sculptor Frédéric Auguste Bartholdi was commissioned to design a statue for the United States. 1884: The statue was completed in France. 1885: The statue arrived in New York Harbor. 1886: The Statue of Liberty was dedicated. 1924: The Statue of Liberty became part of a national monument.

The timeline should show the following differences:

• The difference between the time Bartholdi was commissioned to design a statue and the time it was completed was about 8 years.
• The difference between the time the statue was completed and the time it arrived in New York Harbor was about one year.
• The difference between the time the statue arrived in New York Harbor and when it was dedicated was about one year.
• The difference between the time the statue was dedicated and when it became part of a national monument was about 38 years.

#### Student Report

The letter back to Robert Diaz gives students an opportunity to show what they have done.

#### Extending the Investigation

Have the students create timelines for another series of events and calculate the difference between pairs of dates.