My daughter has really been enjoying They Might Be Giants' "Here Comes Science" album on youtube. She's been watching them over and over and gets mad if we turn it off... Here is one she (and her mommy) really likes. I figure this helps balance out the stuff she hears on Sunday. ha.
If you enjoyed that, I might also recommend, Meet the Elements, and The Sun is a Miasma of Incandescent Plasma, and I am a Paleontologist.