Remeber Larry Sanger? He wrote an awesome comment on the recent Today Show segment on YBCR. He is one of the co-founders of WatchKnow. I’ve cut & pasted this little blurb from their “about us” section on their site. If you haven’t visited this site yet, I suggest that you do. Budget some time though, because you may be come addicted 
There is SOOO much available to teachers here. On the left is their directory. If you slide the little age tab you can narrow down your search to an age bracket that is most suited to your child’s learning in any particular subject area.
"WatchKnow has indexed over 15,000 online educational videos for children, putting them into a directory of over 3,000 categories. The videos are available without any registration or fees to teachers in the classroom and to students at home 24/7. You can dive into our innovative directory or search by subject and age level. Video titles, descriptions, age level information, and ratings are all edited for usefulness. The site invites broad participation in a new kind of wiki system, guided by teachers. We have had a tremendously positive response from educators to the website.
WatchKnow is a project of the non-profit 501(c)(3) Community Foundation of Northwest Mississippi, and is directed by Dr. Larry Sanger, best known as co-founder of Wikipedia, and edited by a group of editors and assistants, all trained as educators."