Vegetables; paint and paper.
A good activity for a day when you are cleaning out your refrigerator. Do you have a wrinkled red pepper in there? Some floppy broccoli? Sprouted potatoes? They're not good for eating, but they are good for a little art project. Instead of the usual paint brush, have your preschooler use these to make interesting textures and shapes in their paintings. (A cut up pepper makes particularly pretty shapes.)