Discipline: 5 minute deduction

My name is Nathan and I teach in Korea.
I have found this works quite well for ages 10-15. At the start of the class write 5 marks on the board with the title 'game'. Each of the marks represent 5 minutes of game time, my kids go nuts for games. If any student talks, misbehaves etc. then take 1 mark off. All of the other students in the class will do the disciplining for you when they see that their classmate has lost them 5 minutes of precious game time. It rewards kids for effort and allows for a bit of fun while studying.