One of the biggest concerns that coaches and associations have these days is with pitchers and the care of their arms. Ultimately it really is the coach that needs to watch this but parents, associations, leagues, all have different thoughts and recommendations. I ran across this article from USA Today  that has some nice information, and while it's not the only thing it certainly is something to consider.  One side note in this conversation you as a parent must be aware  of how much your son or daughter is pitching because many times  a really good pitchers is playing on more than one team  and therefore can accumulate  more pitches than he/she should throw within a time. Because it's league is only keeping track of that one so you could even get caught up  and throwing double what the boy/girl should be allowed. He was a parent need to monitor this.

 I have a grandson that played in California, there league went so far as to count 35 pitches against the catcher  if he came into pitch. And there league which was 14 and under if a catcher came into pitch  he automatically had 35 pitches against out of the 70 possible so this is even a case of a league going a little further  toward pitch count and arm care.

It is interesting to note that because of the arm motion softball pitchers can and do pitch huge number of  pitches with no arm problems while we should be cautious  there are no recommendations for softball, the pitcher will tell you by just looking, listening, and using common sense.

 This one came from US a baseball medical and safety advisory committee:  and published with their permission.

USA Baseball Medical And Safety Advisory Committee Guidelines
Age     Max Pitches Game     Pitches Week

8-10       50       75
11-12     75       100
13-14     75       125
15-16     90       2 Games Week
17-18     105     2 Games Week

Ages To Learn The Different Types
Pitch Type     Age To Learn

Fastball           8
Changeup      10
Curveball        14
Knuckleball     15
Slider              16
Forkball           16
Splitter            16
Screwball       17

Survey Of Types Of Balls Thrown ~ Ranked Least To Most For Pain Caused

    Fastball
    Changeup
    Curveball
    Slider

Survey Conducted By Dr. Joe Chandler, Team Physician, Atlanta Braves on 101 Braves Hurlers In 2000