About an hour after I made my last post, where I uploaded an embedded YouTube video, I made one of the popup cube wallets. It wasn't that hard. I probably wouldn't have any grade below 4th try it. It would be great if I can get our art teacher to do it with the kids (not sure if he would be willing or not). That way they can work on what goes on the cube in science class. I would like it to be a little bit bigger but I am thinking that I can enlarge the template on the copier. You definitely have to use card stock paper for both the cube and wallet for stability purposes.
Above is a short (30 second) video of my finished cube.
The website for the PDF templates can be found HERE. Scroll down until you see the Pop Up Cube in Wallet video and just below it are the templates.