This hall pass has been a complete game-changer in our classroom. It significantly cuts down on those "non-bathroom-bathroom-trips" and encourages the students to come to class prepared.
I collect them at the end of the quarter and students who didn't use any get a special treat (full size candy bar or 3 extra credit points, for example), students who used less than 3 choose a small piece of candy, and students who used all 3 get nothing - no punishment, but no reward!
AFTER students use all three within a quarter, they are still able to use the bathroom or run to their locker, but they then need to make up the time the missed with me before/after school or during snack break.
Feel free to edit/change/use in a way that will work best for your classroom philosophy and community.