Coach needing assistance with balks

[mattmets]

I don't have the experience of some of the other guys here, but just some very common things I've called in the 5 years I've been working:

• Pitchers who "step off" with their left foot
• Pitchers who come set and separate the hands without making a delivery or stepping off first
• Last year I had one kid who, after coming set, would bob up and down without delivering.

I'll leave it to the other guys to describe exactly what constitutes a balk because they can do it more clearly than I can, but those are the more common balks I've seen/called at the 13-16 level.