http://Science-at-home.org. They made darling little dried apple witch faces. I remember making little old lady faces.
When the apples are dry, use tacky glue to dress up your witch. Add hair, maybe a little witch hat. Some beads in the eye holes and permanent marker to enhance the witch lips.
Ask your child why the apple looks different from a newly peeled apple. Why did the apple shrivel up? (Water evaporated from the apple). Observe the difference between the apple that still had its peel on and the apple that was peeled. How does the peel protect the apple?