Here’s a great site for using songs to help the teaching of Science in the classroom. Simple Science has videos for many KS2 topics with songs, and also explanations of some of the concepts;

Videos are hosted on Vimeo, which means they are higher quality than YouTube, and also means they are accessible in schools that have blocked YouTube.

The videos are free on the website, but if you like them, you might want to buy a DVD of the high quality versions.

4F Electricity Song from Simple Science on Vimeo.