What do you think is the best punishment for this case?

That's how some schools are , worthless teachers that doesn't do anything when the students are in trouble. I doubt if someone actually bride the principal of the school here. You can go around hurting others and then you get 2 weeks of school holiday? Seriously? That's bullshit. But I hope the protest people are making protests of the principal's decision now would change the situation. At least give a little more justice to the poor victim.