The Artist's Toolkit http://www.artsconnected.org/toolkit/
Mr. Picassohead http://www.mrpicassohead.com/
Classics for Kids http://www.classicsforkids.com/
New York Philharmonic for Kids http://www.nyphilkids.org
San Francisco Philharmonic for Kids http://www.sfskids.org/templates/splash.asp