I give my students 3 hall passes every nine weeks. If they don't use the hall passes, they can use them as LATE homework passes (meaning they still do the homework, but can turn it in late for full credit). If they still haven't used their passes at the end of the nine weeks, they can turn them in for a small amount of bonus points. I cut 4 strips of 3 hall passes each. The students keep these in their binder for future use.