Under Pennsylvania law, assuming all your facts to be accurate and provable, you have two basic choices. One is to file a police report and ask the police to consider working with the District Attorney to bring a charge against the coach for criminal assault. Simple Assault is usually a Misdemeanor 2 charge, unless it is an assault by an adult on a child under 12, in which case it is a more serious Misdemeanor 1 (this seems to be the facts in your case).
Or, you can go to the District Justice court in the area where the actions occurred and file a civil case for "Trespass" (the Pennsylvania common law term for a tort complaint). You could represent yourself and present any bills (medical bills, counseling bills, etc) and ask the District Justice to award damages. If there are no financial damages, it does not make sense to bring such a civil action -- there would be no damages to recover.
Sign up to receive a 3-part series of useful information and advice about personal injury law.