http://www.songsforteaching.com/index.htmlI followed a link that led to a link that led to a link that led to another link and found THIS!!!! I'm sorry I can't give credit to the Brillkid's member who started me on this treasurehunt as I've lost track!
I've only peeked through the subject area of math, but there are PLENTY of other subject areas to explore. If you're looking for music to learn by then you may be just as excited about this find as I am
The site gives you tiny samples of the songs and information about ordering them. Enjoy!