Here's an activity I did with my second graders that turned out really well. The kids loved it and the snake sculptures turned out great. The images are of my own samples, but the kids' projects are way better, of course. We watched a little snipped of the jungle book and then looked at some pictures of snakes to get ideas, and then we started making our sculptures!
First we used tin foil to make an armature for the snake. I cut a long narrow piece of foil for each kid and they crumpled them into a long snake, pinched them to shape and then bent them around to make a snake pose.
Next, we wrapped the tin foil armatures in plaster bandages. It only took one layer of bandages to get a good solid sculpture.
Once the plaster bandages dried, we painted the snakes with patterns. This took the kids a couple classes because they were painting so carefully! When they are all painted and dried we're going to mod podge them to seal the paint.