Kids will do better depending on what kind of music they listen to. If you're listening to your normal music, you'll actually get less work done, because you'll be concentrating on the music more than the work. If you listen to something without lyrics, and a light melody, it'll actually stimulate brain waves and make you work better.
Trust me, I did it as a home-based (A.K.A. non-graded and teacher had nothing to do with it) science experiment.
Mozart works best for math.