Bathroom Pass Idea

Here is a great idea to keep track of who is in the bathroom. Keep 2 objects by the door- One for boys and one for girls. I've used stuffed animals in the past. Before a student can ask you to use the bathroom, they have to see if the object is available. If it is, they can ask you permission. If you say yes, they go get the object, take it to there desk and go to the bathroom. I don't have the students carry an actual pass to the bathroom because the bathroom is full of germs. I remember one time, a boy came back, gave the pass to another boy and then let me know that the pass fell in the toilet. Yuck! Do you have any other great pass ideas? Let me know!