[Mkelcy]

File suit against the parents, the principal and the school district on Monday. The complaint doesn't need to be fancy, it doesn't even need to withstand a demurrer. All it needs to do is to get their attention. Have the complaint served on Monday, by a process server, in person, at the school - make sure you sue and serve the principal personally and make sure you allege that he/she has willfully failed to follow district policy. It'll cost you a little to prepare the complaint and to have it personally served, but you want shock and awe.

DO NOT encourage or allow you son to kick the bejeesus out of the other kid. That will only muddy the record, and may expose you and your kid to a world of hurt. The "parents" of the other kid are clearly not suitable to be rearing young, and will only seize on any retaliation to pursue a claim against you.