Corporal punishment in schools was banned for a reason.
Think about it this way. Schools are where children learn things. If corporal punishment is allowed, one of the things they learn is that violence is the solution to bad behaviour. So they learn that every time someone pisses them off, it's ok to beat them up, and effectively that two wrongs make a right.
Also, what if the offence is beating someone up? A student beats up another student, and their punishment is being caned by the head teacher. What kind of message is that sending out? Basically, it says that the powerful can use violence against the weak, and the weak can use violence against the even weaker.