CK-12 Foundation
Ck 12: Earth Science: Earth's Core
[Free Registration/Login may be required to access all resource tools.] Describes the composition of the Earth's core.
Woods Hole Oceanographic Institution
Deeper Discovery: Earth's Anatomy
Interactive site provides information on each layer of the earth. Click on a layer to discover more about it.
Center for Educational Technologies
Nasa: Classroom of the Future: Spheres: Lithosphere
At this site from the NASA Classroom of the Future, you can learn about the many different layers of the earth and see what the earth would look like cut in half.
The Franklin Institute
The Franklin Institute: Earth Bowl
This activity from The Franklin Institute demonstrates the layers of the earth using gelatin, pudding, graham crackers, and a few other items. The students actually construct a representation of the earth that they can eat.
Geography 4 kids
Geography4 kids.com: Composition
Diagrams explain the internal composition of the earth. The mantle and the core are discussed along with the role density played in the initial formation of the layers.