Example from my student teaching: 

Though I faced many challenges while teaching my Math class, my teacher and I established a system of classroom management which worked very well with all of the students. I explained to the students how I was paid for doing my job as a teacher, and how I could lose money when I did not do my job well. I related this to their job as students, and told them I would pass out pennies when I saw them following the rules of the classroom (posted on the classroom door), and take pennies away when they were not following the rules. Periodically, we would have a classroom store, where they would be able to purchase items with the money they earned. I realized how important it was for the students to "buy into" the system right away, so for the first week I handed out money quite liberally. After the week was clearly a success, I discussed with the students how I realized they were capable of reaching higher standards, and began making them go above and beyond to earn their pennies. It was amazing how quickly the class turned around, even after we added eight additional students and began learning more abstract of concepts, which were difficult for the low-level students to grasp. 

I would not hesitate to use this system in another classroom, provided it seemed to work for the individual students of that class. I believe its impact was so large because it relied on positive reinforcement, though it also included consequences for when the students did not uphold their end of the bargain. I especially liked the idea of raising the bar of expectations gradually, so the students feel they have a new goal to work towards and are reminded of the benefits of the system. If I were in my own classroom, I would make the prizes more "interesting," such as free choice seating or an extra dig in the archeology sandbox; however, the candy my teacher provided also worked very well as a motivational tool.