Fun with Sedimentary Rocks
activity exercisesuggested grade levels: 6-8

view Idaho achievement standards for this lesson

The three basic kinds of rock are classified by how each type was formed. This activity will provide a model for students on how sedimentary rock is formed.

1. Students will learn how to use the Digital Atlas of Idaho.
2. Students will learn about how different types of rocks are formed and will do an activity involving sedimentary rocks.

Use the geology basics section of the Digital Atlas of Idaho. To get there: Click on Atlas Home, Geology, Basics, then on Diagrams. Review the diagram and click on the various links to learn about the three basic rock types and how each is formed. Review as a class:

1. The three basic kinds of rock.
2. How each of these rocks forms.
3. The Rock cycle.

Use the simple activity below to increase your understanding of sedimentary rocks:

1. Mix equal weights of sand and dry plaster of Paris. Pour it into a transparent plastic container (such as a clear plastic soda-pop bottle) to make a layer of about one-inch (2 cm). Now add a mixture of fine gravel and plaster. Do the same for various mixtures of colored sand, or pebbles, all with plaster of Paris. Throw in a seashell or two on a layer.
2. Now fill the container with water and leave it over night. The next day you will have your own sedimentary rock. The water will have caused the plaster to recrystallize and cement the whole mass together. The seashells will be present as "fossils".

Handouts/Activity links:
These are links to access the handouts and printable materials.

Related Lesson Topics:
Geology: Geology Topics

Lesson plan by Stefan Sommer and James Scannell, 2001
Idaho Achievement Standards (as of 7/2001) met by completing this activity: