I teach high school students a subject they detest. Because of this, they are always looking for ways to be out of my classroom rather than in it. To combat their excuses, I developed a hall pass plan in which they each get 4 passes to use throughout the quarter. If they go unused, they may bring the passes to class on exam day in order to omit a question from the exam for each unused pass. So they don't omit all the essay questions, I have stated on the pass that three may be used for a multiple choice question and one may be used for an essay. I've found that because these passes have power, they're only used in emergency bathroom situations and the students are better equipped for the exams.
Note: I also print them on card stock so they're more durable than with regular copy paper.