Your best bet at getting the school to pay your son's medical bills is to contact a personal injury attorney.  You may get lucky and the school may have a policy that covers these types of matters.  However, most schools will not pay on these types of claims for two reasons.  The first is because they will argue that the child and parent volutarily consented to activity.  You may have even signed a waiver of liability when completing the forms to play-- but just didn't think twice about.  The second reason relates to immunity.  Texas offers an extensive amount of immunity for school districts.  Kids have left schools with permanent disfigurement and injuries with no compensation because of these immunity rules in Texas.  It is possible, under extreme instances of bad conduct by the school, to overcome school district immunity.  Do not look for just any person injury attorney.  Try to find one that has had experience suing governmental entities, if possible.  They will have more experience in looks for fact patterns that can help with this immunity issue.