How can I keep my dry erase board from falling down?

I am a college student, and as a college student, I have a dry erase board on the outside of my dorm room door. I've tried everything- scotch tape, duct tape, masking tape, those adhesive foam square things, and every combination of those, but the board always falls down. My door is metal, so I can't exactly nail it in or anything, but the paint is so thick on it, I doubt gluing strong magnets tot eh back of the board would work either. Does anybody out there have any brilliant ideas?