A pitch that goes by many names is always a hot topic for discussion especially when it comes to young pitchers.
I found this five-year study by the Department of Exercise and Sport Science at the University of North Carolina in 2008 called The Learning Curve which produced several interesting findings including the following: 1. The relationship between age, type of pitch and injury risk is complex, but there was no clear evidence that throwing breaking pitches at an early age was an injury risk factor; and; 2. The data showed the primary cause of arm injuries is overuse, not the type of pitch. via Youth Baseball Pitching Study Shows Overuse is Primary Cause of Arm Injuries. The study focuses more on pitch count and good coaching on the correct pitching technique along with parent and athlete education as important means of injury prevention.
When I was learning to pitch, I was told not to throw the curveball until you are in high school. Is that true? I like what Billy Ripken states in The Truth About Breaking Pitches on www.ripkenbaseball.com. He states “we know that kids develop at different rates physically and emotionally. My 10-year-old may not have developed the same as yours, so really this decision should be made on a case-by-case basis. You might find a young pitcher who is big for his age and already has developed a good fastball, but who wouldn’t be able to emotionally handle the responsibility of throwing just a few breaking pitches in a game”.
He also states for most young pitchers it is best to throw a lot of fastballs and to develop a consistent change-up. You can win a lot of games through the high school level with a good fastball and change.
My two cents, young pitchers should concentrate on consistent and proper mechanics. Then, can he place a two-seam and four-seam fastball on the corners of the plate. Then, develop a good change up. Watch that pitch count! Once that is accomplished, the discussion about curveballs can begin.