It seems to be a popular way to teach math to older kids, as seen here:
Slope Intercept Rap
Uploaded by capo689 on Apr 22, 2008
Lamar Queen is an 8th grade math teacher in Los Angeles, his methodology of teaching students includes writing and performing songs to reinforce lessons. When we discovered Lamar he already had a whole text book worth of songs and this video that he made with the help of teachers and students at his school. Although it is not polished, we believe in using art and music to teach children almost anything so we are happy to try and bring his mission of education through the arts to a wider audience. Look for more unique learning from Lamar Queen soon.
http://www.youtube.com/v/REjcPZeypVg&rel=1