There is a large amount of educational materials available on the internet. The following links will get you started to some of the more useful sites that I have found.

GCRIO Global Change and Environmental Education Resources
Chemistry Review Directory
SCIENCE IS FUN in the Lab of Shakhashiri
ChemEd: Chemistry Education Resources
WWW.SCIMEDIA.COM - Hypermedia for Science Education.
Chem 1201 Section 2 General Information
Internet Resources: Chemistry
General Organic and Biochemistry
K-12 Activities-Science