Updated: Mar 19, 2019
Here is a fun, simple, process based art project that you can do with your 3-5 year olds. I began by reading them the book Sky Color, by Peter H. Reynolds.
Give them a piece of white watercolor paper. If you don't have watercolor paper you could use any type of thick white paper. Watercolor paper is pricey, so I like to give my kids one sheet of watercolor paper per project, then if they want to do a second one we just use plain old copy paper.
Oil pastels (substitute with crayons)