Problem is...The best hitting coaches in the game today teach their hitters that if the ball "pops" or goes "up" out of the hand, it is a "hanger" or a "spinner" and will soon find a nice resting place over the outfield wall!!! (BTW, if you are teaching your own son hitting, that is the ONLY pitch that moves "up" out of the hand and is easily recognized, once you know what to look for. All other pitches have a "downward" or "straight out" action.)
In order to teach your son how to convert his "spinner" into a "hammer" (and have much more success with his breaking ball), show him this picture of John Smoltz at release.
John's chest is directly over his front knee at release. This is THE key. And the easiest way I have found to teach this is to have your young hurler mentally picture "pulling a string" attached to the middle of his chest at his release point.
This way, the chest almost always extends over the front knee once they "pull the string", and the breaking ball will break hard and down in a "straight out" of the hand manner!
And your son will now be known for having a "Hammer" for a breaking ball and can put the "Spinner" back where it belongs...(in the tackle box!)