On my way back to the car, after feeding the ducks at the park, I stopped at a large tree stump. I remembered that I had sidewalk chalk in the car and I quickly went to get it. Then I just filled the top of the stump up with bright sidewalk chalk.
I felt really good about it. It rained later that night, but everything is temporary in some way, right? I hope that someone got to see it before it washed away.
I think it would be cool to do this on other stumps of the trunks of smooth trees. Beautifying the world.