The Discovery Channel has some great stuff. Check out the following. Very helpful info. I used to assign my students to write a report based on various shows that would be airing on topics we were studying. Over time, they stopped watching other programs and started watching more educational programs.
Every little bit helps.
NOVA Online provides a companion Web site for each week's NOVA broadcast, program schedules, teacher guides, audience feedback, and links to related sites. In addition, NOVA Online joins with PBS to bring you images and reports from live expeditions around the globe. The letter to teachers give some great ideas for how to use the information on the site with kids. Also, some great interactive stuff. Make sure to go to the Inventor's Workshop.