From my own experience, what most teachers do here in China is to call the student home and get either one or both parents to come to school and once there, being informed of the student faults.  I have been thru a couple of those, a waste of time.  One time it was because my child did not turn in her homework one day she was sick and had to be taken to the hospital, so she did not have time to finish it,  Made no difference that we sent a note to the teacher explaining why the homework was not finished, we were still called in.  And when the teacher told me the reason for the call, I asked her if she had seen the note, and she replied yes.  So I asked her what she did not understand about it and the reason why the homework was not done, and the teacher got piss at me.  This is not that my child is a problem child, she holds for years now the highest point average of all the 5 saloons at her grade level.  never fails to turn in her assigned homework.  

But here, if you think children of one child policy are little emperors, teachers think they are kings too in some schools.  And some go as far as hitting the students, one thing I do not agree with at all.

At my school classes have points. One student does something bad and the entire class gets points deducted.

Then there are public gathering during which points and rankings of classes for every grade are given. It's essentially a public shame type of system.

Otherwise they get yelled at. Worst case scenario the parents get a call. That's usually pretty bad. Overall though I'd say they're pretty good with public humiliation. 40 kids per class. If you screw up, you get chewed in front of all 39+ of them, and then the entire class gets chewed up in front of the entire grade (which is over 1k kids at my school). It's pretty effective.

I've seen kids forced to do 50-100 push ups or squats. slapped on the shoulder, this is just for talking out aloud.

Corporal punishment is still rampant but it is usually not exhibited in the presence of the laowai.

The parents can be quite strict with their children when the parents are forced to come to school as a result of their child's purported misbehavior.

Usually Chinese schools cannot permanently expel students for discipline issues, but nonetheless, I have seen that happen too.

I have heard also on a similar note that in many school districts in Texas spanking and forms of corporal punishment have been reintroduced usually with the consent of the parents, although according to the New York Times, sometimes without the consent of the parents.