Type of Lesson: Hands-on Activity, Reading & Writing Exercise
Time Needed: 30 minutes
Earth and Space Science, Grades 5-8: Lithospheric plates on the scales of continents and oceans constantly move at rates of centimeters per year in response to movements in the mantle. Major geological events, such as earthquakes, volcanic eruptions, and mountain building, result from these plate motions.
Earth and Space Science, Grades 5-8: Some changes in the solid earth can be described as the “rock cycle.” Old rocks at the earth’s surface weather, forming sediments that are buried, then compacted, heated, and often recrystallized into new rock. Eventually, those new rocks may be brought to the surface by the forces that drive plate motions, and the rock cycle continues.
Physical Science, Grades K-4: Magnets attract and repel each other and certain kinds of other materials.
Science and Technology, Grades K-4: Tools help scientists make better observations, measurements, and equipment for investigations. The help scientists see, measure, and do things that they could not otherwise see, measure and do.
Unifying Concepts and Processes, Grades K-12: Models are tentative schemes or structures that correspond to real objects, events, or classes of events and that have explanatory power.
2. In order for the students to complete the worksheet, you will need to build two sets of prompts, a sea floor spreading model and an ore deposit model. Depending on the size of your class, you may want to build more than one of each of these models. You may also want students to use their magnetometer on a few different models you've created. No matter what the size of your class, have half of the class start on part I of the worksheet and half of the class start on part II of the worksheet.
A. Constructing a Sea Floor Spreading Model
Open file folder. Choose one side to tape magnets to. On this side, draw 2 lines, that divide the folder space into 4 equal parts (one line should be 11 inches and one line 8 1/2 inches if you are using a standard file folder). Arrange the magnets along the long line so that their polarities are symmetric on each side of the short line. For example, you may decide to place 3 magnets on either side of the short line in this order: N-S-N-line-N-S-N. Another arrangement might be N-N-S-line-S-N-N, etc. Tape the magnets in place. Close the folder and tape it shut as well. Draw the short line on the top of the folder - this represents the mid-ocean ridge.
B. Constructing a Ore Deposit Model
With the folder shut, draw a grid on the top of the folder (suggested 1 inch squares). Open file folder. Arrange any number of magnets anywhere on the bottom portion of the folder. North or south polarity can face up. Tape the magnets in place. Now close the file folder and tape shut.
The answers to the questions on the Student Activity sheet are as follows: C, B, A, D, B, B, A (in the order the questions are asked).
Another use of the magnetometer instrument can be explored using our Terrabagga Activity.