http://www.ncrel.org/sdrs/areas/issues/methods/technlgy/te800.htm#type

http://www.stevespanglerscience.com/

http://www.enchantedlearning.com/subjects/astronomy/planets/earth/Inside.shtml

http://scign.jpl.nasa.gov/learn/plate1.htm

http://www.windows.ucar.edu/tour/link=/earth/Interior_Structure/interior.html

http://www.rocksandminerals4u.com/igneous_rocks.html

http://www.rocksandminerals4u.com/sedimentary_rocks.html

http://www.rocksandminerals4u.com/metamorphic_rocks.html

http://www.learner.org/interactives/rockcycle/

http://education.jlab.org/solquiz/index.html

http://www.educationalrap.com/59/layers-of-the-earth.html

http://www.kn.att.com/wired/fil/pages/webearthscsc.html