Im a volunteer dance teacher for a local studio that gives under privileged children after school activity... Some of the recent songs they really seem to enjoy and have very cute beats and routines are
Mercy-duffy (generally not a child song but Theres an edited version and it has a awesome beat and the kids looooove it)
This is me -demi lovato (inspirational)
The hairspray soundtrack is catchy and great dance beats
and almost any and every disney mania cd is great, its from disney so you know its appropriate
Hope this helps some!