sand & shell art - A co-worker donated a large sack of sand dollars and we water colored on them. We also found a stash of glass test tubes in our closet with no discernible purpose. So, we purchased stoppers and colored sand and let the kids create layered sand art in them. The test tubes were VERY popular with kids wanting to do several of them.
plant pals & food stamping - Using pantyhose, cups and grass seed as a base, we created creatures. Using rubber bands, kids also created facial features like the nose on our sample. Given some water and a day or two, the creatures grow grass hair that can be trimmed.
For the younger set we inevitably get at this school-age program in summer, we put out large stamp pads, paper and cut-up fruit and veggies for stamping. We used the traditional apples and potatoes, as well as celery hearts, pepper slices, and mushrooms.
cave painting & rock art - For a paleolithic art experience, we had kids lie on their backs to create art inspired by cave paintings from around the world. A slide show ran throughout the program to provide inspiration and we displayed books as well.
I found a TON of brown paper sacks in our closet so I cut the bottoms off, opened them up, and used masking tape to tape them under tables. Butcher or kraft paper would work as well. Rather than the usual markers or colored pencils, we ordered a classroom pack of oil pastels and I put out black, white, gray, brown, and red, to keep the look authentic.
For another unusual art experience, I put out some smooth stones and colored pencils. I did rough up the polished stones with sandpaper for a better result. We used the cheap pencil sets we had on hand, though fancy prisma colors create a beautiful product. We also didn't seal them and as a result too much handling did smudge and fade the designs.