I discovered this by accident. It has actually changed my life:
Lip Gloss Song by Lil Mama
The message that "it wasn't the lipgloss, it was you all along" is probably my favorite part.
Another school-themed video: Pop, Lock, and Drop by Huey
I both love, and am disturbed by the teeny girl who does the "pop, lock, and drop it."
And a charming old-school video, courtesy of Slate: Aunt Jackie by Jason Fox