S.S.
here's a trick I learned with my 3 1/2 year old - go to the toy store and buy a small floating toy that is bigger than the hole in the bottom of the toilet (but easily washable, like a duckie or something). Put it in the toilet and tell him to pee-pee on the duck (or orange ring, or whatever you find). It'll be a game to him, he'll get the hang of it, and the toy won't go down the toilet if accidentally flushed! Jacob loves it