Teach the Earth > Rates and Time > Teaching Activities > Geologic and Navajo Time Line

Time line

Margaret Mayer
Dine College
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This activity was selected for the On the Cutting Edge Reviewed Teaching Collection

This activity has received positive reviews in a peer review process involving five review categories. The five categories included in the process are

  • Scientific Accuracy
  • Alignment of Learning Goals, Activities, and Assessments
  • Pedagogic Effectiveness
  • Robustness (usability and dependability of all components)
  • Completeness of the ActivitySheet web page

For more information about the peer review process itself, please see http://serc.carleton.edu/NAGTWorkshops/review.html.

This page first made public: Feb 23, 2012


Students develop a time line using registrar tape and correlating marking off divisions of geologic eras. Above this they develop a Navajo time line of creation. Each week they focusing on the topic (era/period) of the week adding major events in a creative manner such as drawings and marking subcategories of time.

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For GLG 102 Historical Geolgoy undergradate majors and/or non-majors gen ed course

Skills and concepts that students must have mastered

How the activity is situated in the course

It is a continuous activity throughout the course (each week) besides another lab


Content/concepts goals for this activity

Higher order thinking skills goals for this activity

Other skills goals for this activity

Description of the activity/assignment

This lab serves to introduce students to geologic time and serves as an outline for the course through the semester.

Students use a tape register and must mark out the corresponding length of each Geologic Era and Eon towards the beginning of the course. Above Western time line Navajo students construct their own time line correlating events as best as possible. As the course progresses starting from 4.6bya each week they must draw major events that occur marking correct subdivisions of time and ages ago. As fossil life gets more complex such as beginning in the Paleozoic students are must take different categories of fossils or different periods so all are doing different things but working together. (Similarly the Navajo time line builds. This time line is taped around the room—and I would have liked to paint the two time lines along the corridor of the building but Maintenance axed it.

Determining whether students have met the goals

Students must interpret their time lines each week (Western and Navajo) The time divisions must be accurately marked off and major events drawn or indicated in a creative way.

More information about assessment tools and techniques.

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Supporting references/URLs

This on-going semester long lab is a take off from the 1 period lab developed by Dr. Steve Semken, ASU.

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