Ask an Astronomer
Delightful video podcasts for use with students. Topics range from the movement of stars to the status of Pluto to black holes. Each video is done by a NASA scientist and provides excellent information. The videos can be downloaded in various formats for use b educators and students.

Why? The Science Show for Kids Podcast
Check out interesting options done by a professor in Canada. Topics range from "Why do you have 5 fingers?" to "What Happened to the Dinosaurs?" to "Why Isn't Greeland a Continent?" Well done for use with students.

Superb video podcast for helping teach biology. Check out the podcast on the "Most Deadliest Snake." Uee Itunes to subscribe for ease of access and download options.