what about some thin, pliable sheet metal? i know you can get that stuff at home depot or lowe's, but not sure how easy it is to cut. if it's going to be covered in fabric you could easily pad any sharp corners and edges.
That may work. I worry about it being too flexible, I don't want the thing I made to break in half.
I would love to have a 1/4" piece of rigid plastic like what those Little Tykes outdoor toys are made of.
This past weekend we made swords and throwing knives out of wooden yardsticks and paint stirrers. That was fun! I cant wait to paint them. I'll post pics of that when we're done.