Earth Learning Ideas

Incredibly useful site for small to medium sized Earth Science lessons and activities:
http://aegsrv2.esci.keele.ac.uk/earthlearningidea/English/contents_English.html
http://earthlearningidea.blogspot.com/

The lessons are well explained and well researched. However, the resources are often lacking (ie. lacking in easy to use presentations).

Berkeley Space Lab and WISE

http://cse.ssl.berkeley.edu/cms/

This is one site that I'm going to file away for future lessons on space (coming later in the semester). They have a bunch of slick-looking media and a number of classroom ready lessons.

There are also some good meteorology and atmospheric sciences lessons.

On Berkeley's WISE there are two promising activities - one involving planetary motion and the other involving plate tectonics.