Well don't attack the kid. Tell his parents that there is a serious problem and that you need to have a face to face talk to them to try and resolve the money problem in all this.. its going to cost at least 350 dollars just for the glass so a grand total of 400-450 is reasonable. If its not a huge deal I guess you could replace it yourself, but mostlikely it will be a good idea to contact his parents but not to get him in trouble as it was an accident.