hate to disappoint you, but they wont host your videos no matter how great of a teacher you are. If you have looked at a bunch of their videos, you might have noticed that they are all done by one guy! Hence the name Khan Academy. The whole site is from the crazed brain of this one guy.

You can see him talk in person in this TED talk: http://www.ted.com/talks/salman_khan_let_s_use_video_to_rein...