The coolest thing happens when you dab a little dish soap onto the surface of 2% or whole milk that has some food coloring drops on it! The colors expand away from the cotton swab that it looks like small explosions of colorful swirls. The science of this art project is what makes it really interesting. And the results are well worth photographing — maybe even printing enlarged copies and framing these fun works of art. Try this with kids of any age. It’s super easy and takes few ingredients.