Quantitative Skills > Teaching Resources > Activities > Reading Topographic Maps and Calculating Map Scale

Reading Topographic Maps and Calculating Map Scale

This page was developed by Leslie Kanat from Johnson State 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 a review and suggestion process as a part of an activity development workshop.

This activity has benefited from input from faculty educators beyond the author through a review and suggestion process as a part of an activity development workshop. Workshop participants were provided with a set of criteria against which they evaluated each others' activities. After the review, the authors developed a plan for revising their activities based on the feedback they received from their peers. To learn more about this review process, see http://serc.carleton.edu/quantskills/review_processes.html#2006.

This page first made public: Nov 14, 2006


Students will use a topographic map and define the watershed drained by Joe Brook, draw a bar scale, and calculate a ratio scale.

Learning Goals

Students will be able to:
  • apply quantitative skills to solve map scale problems
  • discover the meaning of a watershed

Context for Use

This homework assignment is appropriate for an introductory level, general earth science course that requires an understanding of map scales. Students will need prior experience working with bar scales and map scales, and have a cursory understanding of the meaning of a watershed. The activity can generally be completed within one hour.

Description and Teaching Materials

The instructor should work with a variety of topographic maps prior to assigning this activity. Only one .pdf file is needed for this assignment.

Assignment handout (Acrobat (PDF) bytes Jun25 06)

Teaching Notes and Tips

Instructors should demonstrate how a map bar scale can be used to calculate a ratio scale and how a ratio scale can be used to draw a bar scale. Examples should use a variety of map scales; the mathematics, and proper use of cancelling units, should be demonstrated a priori.


Instructor should carefully trace the proper watershed on each assignment and make careful notes about the quantitative reasoning skills applied by the student. Once the assignment is returned, the instructor should present the correct format in front of the entire class.

References and Resources

General introduction to topographic maps: http://topomaps.usgs.gov/

Ratio scales defined by the Geology Department at Idaho State University: http://geology.isu.edu/wapi/geostac/Field_Exercise/topomaps/map_scale.htm