How can I get them to shut up for good?

Basically bullying, huh.
Personally, a little chat with the policemen helped, but idk if it'll work where you are.
Otherwise, the principal might help.

ok

A gun would shut them up (im in a dark mood right now)

Lol I wish

Stick a can of shaving cream in the cracks of their lockers and spray till it runs out

tell them to shut up

I have that same problem, Except one of them lived on my street, and I litterally cut open his sister with my nails. It was great until their mom came up to our house and started complaining. But she didn't care about the abusive stuff that her children did to me. And when i tried to explain about some of the stuff the did to me, she asked them about it, and they just lied about it so they wouldn't get in trouble. And then there's another one, and she does stuff to me, like calling me names, an pushes me for no reason.

just tell them to shut up and make a snappy roast comeback

Beat ‘em up

Nukes