I use these bathroom passes in my classroom and tie in classroom management with them. I printed them on colored paper, cut them out, and whole punched them at the top and put them on a binder ring for each student. I printed them on different colored paper for each month. So, the blue passes were for January (6), pink were for February (6), green were for March (6), orange were for April (6), and yellow for May (6). I gave them 6 for each month to use because my students in particular use the restroom to leave class and play! This way, they can only use the restroom alone (we go as a class once in the morning and once in the afternoon) less frequently. You could do more as your wish. Whatever passes were left at the end of month they would turn into me for extra Class Dojo points (which they LOVE), this makes them think twice about wasting their pass to play in the bathroom!
This is a Word Document so that you can edit the teacher name/class number/grade level to fit your classroom.