I’m not a doctor so I am not going to pass judgement on the age at which young players should be throwing a curve ball.  I’m sure that the proper age varies based on many factors including the mechanics and the maturity of the pitcher.

One thing that is for sure, however.  Kids are going to throw curve balls so why not teach them the proper way to do it.

Roy Halladay's curve ball

Here’s some tips on what to teach.

The Curve Ball Grip

• There are several grips to throw a curve ball, but all keep the middle finger and thumb on the seams.
• All of the pressure is with the middle finger and the thumb.
• The pointer finger does not give any pressure and is merely used as a guider.
• The pointer finger and the middle finger should be close together.
• The grip should be further back in the hand than a fastball, but likely not as far back in the hand as a changeup.

Arm Position on Curve Ball

• Teach that the arm position on a curve is exactly the same as a fastball up until the position where the hand reaches the ear of the pitcher.
• At the top of the motion, the wrist wraps the ball and the wrist is facing the ear of the pitcher.
• Be sure that the elbow is higher than the shoulder on a curve ball.  This will create maximum break downward.  If the curve ball is thrown from the 3/4 arm angle, the ball will tend to break more horizontally across the strike zone which is not preferable to a 12-6 curve ball with downward bite.

Wrist Action on Curve Ball

• On a fastball, the wrist is facing the catcher once it reaches the top of the arm point; on a curve the wrist is facing the head of the pitcher.
• Twisting the wrist in the fashion of twisting a door knob is not necessary.  Rather, the pitcher snaps the wrist downward while spinning the thumb upward to create maximum spin.
• The wrist should never be in the position of being parallel to the sky similar to screwing in a light bulb.  This is what causes elbow injury.

Follow Through on a Curve Ball

• The release point on a curve ball is at the front of the bill of the cap.
• The pitcher’s arm actually accelerates from the top of the throw through the follow through.
• The follow through should end higher than a fastball, at about the upper leg of the pitcher’s opposite side.