For an art curriculum this term, we did Usborne's Art Book About Color, which has great information about art history and colors, paints and styles. Each week or so, we would cover a topic in the book, which was sometimes about a single color and had info like what it used to be made from, how artists used the color and how durable the color was over long periods of time. Other topics were about color mixing and styles like pointillism.
For the colors, we had the kids do a single-color project that sometimes included mixed media.
some mixing of colors
these were a form of pointillism or using dots to create a picture. Olivia's, in the middle, was excellent. The boys were good, too, but they each only did one element of the painting in dots. Gabe's was rain and Ezra's was the leaves on the tree.