I keep saying this on reddit. Assault is assault. And assault is a criminal offence as per IPC. You have full right to submit an FIR. For any form of asault.
How seriously it is taken or enforced is a different thing. If you have money you can pay the cops to go threaten and they will oblige depending on how much you pay because it is legally okay for them to do stuff like question the perpetrator or talk to the principal. Police getting involved the school will take it more seriously.
If it was someone rich or powerful they would have done it already.