For the teachers out there:
This is a research article describing the "Good Behavior Game". Basically you divide your classroom into teams. Set specific rules and when any rule is broken by a single student their group recieves a point. The group with the least points at the end of the day gets a reward. If multiple groups have the same number of points then both groups get the reward. It sounds very interesting! The rewards can be pretty simple: going to recess a little earlier than the other group, a special project, class helpers, etc.