DD5 and DD4 both do this until I feel like my head is going to explode. My solution is to give them something to do. What works with them is something to learn, so when they were younger it was count to 100 by 1's, 2's,3's,4's ... or spell words now its times tables and division once I get them started on something they go at it until it's learned, gives me time to keep sane.
I tried this and it doesn't work for my son. If I give him anything to do, he wants to talk about it before he does it, while he's doing it, and after he has finished.
HA! That's about it, too. Ds6 *never* stops talking. I admit to tuning out sometimes, until I realize I've made one "uh-hunh" too many and agreed to something I shouldn't have!
He will, though, often be redirected by math or a word game and is much happier because of it. It gives some form to his energy!
