Don't let the kids upset you; remain calm and keep your voice even. Don't make threats you can't keep. Remove them immediately when they misbehave as a consequence of their behavior. Makre sure they understand consequences before you implement them, then make good on your word.
As a teacher, I see many character problems that could be prevented. Mean what you say. I see parents telling children not to do something and then turning their backs.
There is always the old fashion way of spanking and when its done in public they tend to get embarrassed. Otherwise, taking things away like toys, T. V.
