Teach the Earth > Introductory Courses > Activities > Fun with foam, demonstrating strike and dip in class

Fun with foam, demonstrating strike and dip in class

Angela Moore
Guilford 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 activity has benefited from input from faculty educators beyond the author through a review and suggestion process. This review took place as a part of a faculty professional development workshop where groups of faculty reviewed each others' activities and offered feedback and ideas for improvements. To learn more about the process On the Cutting Edge uses for activity review, see http://serc.carleton.edu/NAGTWorkshops/review.html.

This page first made public: May 15, 2008


Colorful foam sheets are used in a classroom or lab setting to introduce students to the concept of strike and dip. It is interactive, and the instructor or TA's can quickly see which students are 'getting' it and which might need a little more individual assistance.

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I use this activity in introductory courses, including our equivalent to Physical Geology, and in Historical Geology. I've also been known to use it in Structural, for students who might need a refresher at the beginning of the course.

Skills and concepts that students must have mastered

The concepts of strike and dip should have been introduced, and also the basic fold shapes if you plan to include that in the activity.

How the activity is situated in the course

This is a short, fun exercise that is either done in a lecture setting or as the early part of a lab that introduces concepts of basic structural geology (faulting, folding, etc.).


Content/concepts goals for this activity

This activity is designed to help students really understand the concepts of strike and dip. By the end of the activity, students should be able to use the foam to 'model' what a bed would be doing given a basic description (for example, 'a bed has a strike of N45E and is gently dipping to the SE'). Additional concepts that can be introduced include the trend and plunge of a fold axis, or just the recognition of basic fold types.

Higher order thinking skills goals for this activity

This exercise isn't really designed to develop the higher order thinking skills, to be honest, it is more to help cement a basic idea that can then later be used for more in depth interpretation of structural features.

Other skills goals for this activity

This exercise can be done with individuals or with groups; if chosen as a group activity, it can certainly foster supportive interaction among students as they assist one another and participate in both teaching and learning.

Description of the activity/assignment

Colorful foam sheets are used in a classroom or lab setting to help students understand the concept of strike and dip. To prepare for this exercise, students should be introduced to the basic concepts in a short lecture beforehand, and perhaps shown diagrams to give them a general idea of what the terms mean. The instructor will need to identify the N,S,E,W directions in the classroom; it is usually helpful to post sheets with this information and attach it to the walls. The students are then asked to use their sheets of foam to simulate the orientation of beds that are have a specific strike and dip. Once that has been mastered, the exercise can be expanded and students can be asked to demonstrate the trend and plunge of simple folds.

Determining whether students have met the goals

This exercise is interactive and visual, and the instructor or TA's can quickly see which students are 'getting' it and which might need a little more individual assistance based upon how their orient the foam. Care must be taken not to single out students, but in my experience it has been helpful to ask students to assist one another.

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