just outbox them. bust them up with stiff jabs and hard bodyshots when they get wild and they will learn quickly. you can knock them out but only with a bodyshot or by making them quit, dont knock them cold.
dont let them get away with their bull**** either, like i said outbox them and make them pay for being sloppy. show them that timing, distancing, thinking and proper technique beats brute force and aggression every time.