It depends where you hit the kid, the reason, and the method. A smack on the a** for breaking a vase by accident? Not really something to warrant corporal punishment.
A smack on the a** because they did it on purpose? Yeah, alright.
Currently there's a big debate on bringing corporal punishment back into schools in Australia. A lot of teachers think it's the right way to do things because kids are never going to learn to not misbehave. Personally, I think corporal punishment in schools doesn't really teach children anything, in your future years when you're working upto or in a career, you could have an a*****e for a boss, but if s/he so much as touches you, it's enough to warrant a lawsuit. If you ******** up at a job when you're a teenager, the manager/boss will scream and probably fire you, but they're not going to hit you. If kids are going to ******** up at school, we might as well tell them they have the choice to wise up so they might have a better chance in getting into things like college, or tell them where they could end up if they don't get their s**t together. Back in High School, once you got to the senior years here, the rule was basically "Shut up, or get out of my classroom." It was great because there were a lot of people who got kicked out of the room, and some actually started to pay attention after a while, and some just didn't come back, so the teacher's job was somewhat more efficient. It was a big help back in Textiles class where there was literally no time to stop to piss around with anyone, we had a deadline for our Major Project and this one girl would piss around and try to chat with everyone and by the end of it we pretty much just told her to get lost because we were all about ready to jump off a bridge with the amount of stress that was involved between sewing and juggling the written component.