Chemistry

Links
http://www.scienceman.com/pgs/links_chem.html

Periodic Table
http://www.bayerus.com/msms/fun/pages/periodic/index.html
http://www.webelements.com/webelements/scholar/index.html

http://chemsense.org
http://www.iit.edu/~smile/cheminde.html
http://boyles.sdsmt.edu/subhead/welcome.htm
http://www.chem4kids.com
http://antoine.frostburg.edu/chem/senese/101

Kitchen chemistry
http://pbskids.org/zoom/games/kitchenchemistry

Java applets
http://mc2.cchem.berkeley.edu/Java