In regard to the egg carton airplane mentioned in the fist post. We used them with a bunch of young kids. We had a competition for trying to fly them through a hula hoop. It worked very well. This was sponsored by the Stanzel Museum. Stanzel got all the egg cartons for us to use. A few days before, I bought a carton of eggs where I don't usually shop, and realized it was not suitable for making an airplane. Called Stanzel, and, sure enough, they had the wrong kind. That was corrected. Just a matter of luck, I suppose, as I didn't know there were different kinds of egg cartons. I think there was a later article about making a different kind of airplane out of egg cartons.