I happen to be a very strong believer in corporal punishment. I was paddled both at home and at school and turned out to be a respectable person. With that said there are plenty of caveats...
First, the school should not be spanking children. That's the parents job. (see story below)
Second, never paddle a child out of anger. If the kid deserves a paddling, he also deserves it to be administered in a non-abusive way.
Third, if the kid threatens a phone call to the police, offer to dial it for them. Police aren't stupid and when they hear/see the truth, they'll know it. Again, NOT acting in anger will play a big part here. I actually had this happen. The police supervisor, after hearing what had happened, looked at my step-son and said "son, it sounds like you needed exactly what you got". Neither of the kids ever threatened to make that phone call again.
I helped raise my ex's 2 kids from the ages of 9 & 11. Despite the fact that they came out of an extremely unstructured environment, I only spanked each one once. The rest of the time though, they knew it was always an option they didn't want to explore!
So the school story....
In 8th and 9th grade, I attended an old junior high in a smallish town of about 40,000. Every afternoon, various coaches and male teachers would walk the halls and yank guys out of class for a SOLID paddling (5-6 "licks"). No reason was ever given, this was their "fun". The crafts teacher was always there with a freshly fabricated fiberglass paddle, cleanly drilled with various size holes to give it that "added touch", as well as polka dotting your ass! I'll tell ya this...I went home with a severely bruised ass many many times. It came to a head one morning when I was getting dressed for school and my mother walked in. Of course, she didn't believe that I really hadn't done anything, so off to the school we went to have a visit with the principal. A certain male science teacher was called in to explain, and well...since our family Dr. was also the Super of Schools, shit hit the fan and they never laid another hand on me. I will say this, the first few times I got paddled, I was the last one in line and was freakin' petrified...and every single paddling hurt like hell. I would never want my children or others to have to endure that. The pain could be excruciating at times.
Given the way the whole machismo/testosterone thing came into play, I'll say again, no CP in schools...too easy to get out of control...
And IMHO...spank your kids, but only when really necessary and with a calm head....it can be just as useful as any other form of punishment.