Earth's history in 4.56 meters: constructing a timeline with calculator tape

Eric M. Baer based on material from Baer et al. (1999)

Highline Community College
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This page first made public: Aug 1, 2006


A student activity. Students make a timeline of Earth's history using calculator tape. The tape is 4.56 meters long, so that one billion years is one meter. This activity is designed to have students get an introduction to the scale of Earth's history, gain a familiarity with some major events in Earth's history, learn about scaling, the metric system, and large numbers. This material helps illustrate the concepts of deep time and large numbers.

Learning Goals

Context for Use

I use this as a short activity in a introductory geoscience class, early in the term. This takes roughly 45 minutes to an hour with introductory level undergraduates and works best when students work in groups of no more than 2. My classes have 24 students, but I think it would be doable with up to 50 if you had the space. It does help if there is enough supervision to catch mistakes as they happen rather than when students finish since mistakes will propagate along the timeline. You will need calculator tape (available at any office supply store) and meter sticks. Having long tables or open floor space is needed.

There are a couple of places where students can run into trouble.

Teaching Notes and Tips

I recommend that the students answer a couple of basic questions before beginning. This will greatly speed the activity. These could be given as homework.
  1. How many millions are in a billion?
  2. In this activity, you will make a timeline 4.56 meters long that represents 4.56 billion years of Earth's history. How long would 1 billion years be on the timeline? How many years would 100 centimeters represent? How many years would 1 cm represent?
  3. Draw a line 1 cm long.

Teaching Materials


Assessment of this exercise can be unwieldy if the timelines are collected and later evaluated because each one will have to be unrolled and re-rolled. I recommend that each student present their timeline briefly to the assessor when they finish. Then the creator is responsible for unrolling and re-rolling the timeline. I grade on accuracy and completeness.

References and Resources

Derived from Baer, E.A., Baer, E.M. and Whittington, C. 1999. Laboratory Manual for Physical Geology, Revised Printing. Kendall/Hunt, Dubuque IA.

Controlled Vocabulary Terms

Subject: Mathematics, Geoscience:Geology:Historical Geology
Resource Type: Activities:Lab Activity, Classroom Activity
Special Interest: Quantitative, Geo2YC- OLD DO NOT USE, 2YC:Geo2YC
Grade Level: College Lower (13-14):Introductory Level
Quantitative Skills: Problem Solving, Graphs, Models and Modeling, Probability and Statistics:Describing Data Distribution
Ready for Use: Ready to Use
Earth System Topics: Time/Earth History
Quantitative Skills Activity Type: Classroom Activity, Lab Activity
Topics: Time/Earth History
Theme: Teach the Earth:Teaching Topics:Early Earth, Teach the Earth:Teaching Environments:Intro Geoscience, Two-Year Colleges

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