When I was a youngling, I made my own gun by gluing 4.5 popsicle sticks and a clothespin together.  It shot a rubber band about 10 feet.  In the fourth grade I brought it to school and a teacher took it, and I had to talk to the principle to get it back at the end of the day, with a promise not to take it back to school.  I probably broke it after that, I don't really remember.