Earth's Magnetic Field CogSketch geoscience worksheet

Bridget Garnier
,
University of Wisconsin-Madison
Author Profile


Summary

Sketching activity that uses a sketch-understanding program, CogSketch. To draw attention to the changes in magnetic inclination with latitude on Earth, students move, rotate, and match packages of "rock" (that contain indicators of magnetic inclination) to the latitude with the same magnetic inclination.

Used this activity? Share your experiences and modifications

Context

Audience

Undergraduate introductory course in geoscience

Skills and concepts that students must have mastered

Students should have learned about Earth's magnetic field and magnetic inclination.

How the activity is situated in the course

We have used this activity as a homework assignment after the topic is introduced in lecture and reading, but it could also be used in class, in lab, or as group work.

Goals

Content/concepts goals for this activity

Earth's magnetic field, magnetic inclination

Higher order thinking skills goals for this activity

Movement over time

Other skills goals for this activity

Description of the activity/assignment

This worksheet helps students visualize Earth's magnetic field, shows how magnetic inclination changes with latitude, and shows how rocks can be tied to specific latitudes of origin based on magnetic inclination recorded in the rock. In this worksheet, students are given a diagram of the Earth with its magnetic field and 8 packages of "rock" with magnetic inclination arrows. Students grab, move, and rotate each rock to determine its latitude of origin by matching the arrows in the "rock" with the magnetic field lines on the diagram of the Earth. By allowing a direct, physical comparison of the magnetic field to magnetic inclinations recorded in rocks, this worksheet reduces the cognitive load of visualizing those spatial relationships. The worksheet includes a problem that walks students through the process of determining movement of a plate that has two bodies of rock with different magnetic minerals.

This worksheet uses the sketch-understanding program with built-in tutor: CogSketch. Therefore, students, instructors, and/or institution computer labs need to download the program from here: http://www.qrg.northwestern.edu/software/cogsketch/. At any point during the worksheet, students can click the FEEDBACK button and their sketch is compared to the solution image. The built-in tutor identifies any discrepancies and reports pre-written feedback to help the student correct their sketch until they are done with the activity. Once worksheets are emailed to the instructor, worksheets can be batch graded and easily evaluated. This program allows instructors to assign sketching activities that require very little time commitment. Instead, the built-in tutor provides feedback whenever the student requests, without the presence of the instructor. More information on using the program and the activity is in the Instructor's Notes.

We have developed approximately two dozen introductory geoscience worksheets using this program. Each worksheet has a background image and instructions for a sketching task. You can find additional worksheets by searching for "CogSketch" using the search box at the top of this page. We expect to have uploaded all of them by the end of the summer of 2016.

Determining whether students have met the goals

CogSketch has a gradebook feature that allows instructors to batch grade worksheets using the defined rubric in the worksheet. Once graded, instructors can also open all the sketches and evaluate student work. Instructions are given in the Instructor's Notes.

More information about assessment tools and techniques.

Teaching materials and tips

Other Materials

Supporting references/URLs