We used duct tape to make the belts. The best way to do this is to run the duct tape between to metal bar stools, or two kitchen drawer pulls, sticky side up (note: doing it on wood can ruin the finish of your furniture). Then slowly tape another piece of duct tape to the top, remove from stools and fold over ends.
Then make your super hero belt buckles. We used the school colors and the teachers initial. Make the shape you want and then trace it over and over for how many you plan to make. We chose the superman shield shape. An oval would work well too. Cut out of nice card stock and glue together. Duct tape the buckle to the belt. We taped them together by using two pieces of duct tape behind the buckle, one at the top of the shield and one behind at the bottom, rather than a loop tape stuck to the back.
The teachers loved them! Some tied them on and some taped or stapled them on. They were about a yard and a half long for a one size fits all. NOTE: when buying the fancy duct tape you can only get about 5 out of that roll, with no mistakes. I'd stick to regular.