Geologic Time Discussion Analogies

Noah Fay
Pima Community College
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This is 4 ppt slides used to facilitate discussion w/students about the immensity of geologic time. I ask them a series of leading questions and try to get them to do "mental math" in order to grasp the immensity of billions of years.

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This is an introductory physical geology course at a community college. The course does not have any prerequisites and most students have never had any earth science before.

Skills and concepts that students must have mastered

Being awake in class.

How the activity is situated in the course

Stand-alone exercise at the beginning of class discussion and lab activities.


Content/concepts goals for this activity

Immensity of geologic time

Higher order thinking skills goals for this activity

Estimation, comparison, and using analogies

Other skills goals for this activity

Description of the activity/assignment

The slides provide a fun way of discussing the immensity of geologic time and help to grasp the age of the earth, the time gaps between major geologic events, and the relative minuteness of humans time on earth. After the discussion with the class, students are given opportunity to develop their own analogies using "everyday" things (other than the calendar and money examples used in this activity).

Determining whether students have met the goals

Class discussion of student contributions (see above)

More information about assessment tools and techniques.

Teaching materials and tips

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