Lots of people talk down to little kids and treat them differently. Not here at WFMU where we've always played lots of kid created music. Jr and the Soulettes (real audio link) are a long time favorite as are the mighty Eyeball Skeleton. David Soldier and Da Hip Hop Raskalz got lots of airplay last year and that recent Home Schooled comp on Numero is also worthy of mention.
And now from Spain there's the meterRruidos, a group of 4-11 year olds making some noise pieces that would not be out of place on a few shows here at the station. Last Visible Dog, watch your back.