I have a little tree in my front yard that produces the most wonderful seed pods...
Looking at the tree one day I had a light bulb moment...couldn't I make something out of those pods!?
I imagine that there are lots of different seedy type things that would work for this...and kids get a big kick out of the crayon part of the project.
A side note...I picked a few of these when they were green thinking they would turn brown, but they dried a beautiful green colour! If you are wondering this is a silk tree - or Albizia jullibrissin
So, go and find some seeds and get your old crayons and make something. Let me know what exciting seeds you used!