Ellie is 24/25 months old
We started incorporating that idea into painting. We did one for purple, orange and green. The setup was similar for each one -- two colors of tempera paint on a paper plate, a piece of paper for her to experiment with, and color-coordinated tools (either one of the primary colors or secondary color we were making).
Purple -- red and blue paint, with a blue loofah and red roller. Ignore the yellow sponge -- that was from painting Christmas ornaments, which is how this whole thing started.
Orange -- yellow and red paint, with a red scraper and a slice of an orange, flower-shaped pool noodle.
Green -- yellow and blue paint, with a blue scraper, yellow and blue paintbrush and blue and green scrubber. She spent most of this time painting her arm. I can't entirely blame her, as these didn't mix into a very pretty color of green.
Here are the final products -- orange, green and purple.