this website is the BOMB!!! 

http://mindrap.org/media.htm

MindRap is a project of Tiz Media Foundation that facilitates the design and development of rich media content inspired by hip-hop culture for the purpose of exploring math and science concepts to educate and build confidence in at-risk high school students. The program, which has been successfully tested with several pilot partners and student groups, includes core components of song-writing: story-telling, poetry, rhyme, beat, art/music fundamentals, performance, and multimedia.
I particularly like the Algebra song..
Be sure to hit the button for "using more than one property" to get all modules to play in sequence