At the beginning of the week, students are given 5 bathroom passes to use for visiting the restroom or getting a drink, on which they write their name. The student must give the teacher a pass in order to leave the room and it must be an appropriate time, i.e. not while teacher is teaching, testing, group work. At the end of the week, any remaining passes students have are put into a container and one is pulled out for a special prize. To prevent "extra" passes being made, I print the tickets on colored paper. Also, to not waste paper, I make the tickets very small. Each child is responsible for their own tickets: no extras will be handed out and none can be carried over from week to week. It sure controlled those extra trips to the water fountain!