I give one of these to students at the beginning of the year, they are are responsible for keeping track of their card and presenting it to leave the room for the bathroom and/or water. They get 3 passes a semester. Issuing these have cut down on the number of bathroom breaks during my class. The second page is a disclaimer page. Print these out double-sided, so the disclaimer is on the back. I'd recommend printing one out, so that you can write your name on the card and then make the number of copies you need. They are business card sized.
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