We came across this simple and really fun experiement to demonstrate capillary action using toothpicks on this website: https://thestemlaboratory.com/magic-rainbow-toothpick-star/ It was really easy to setup using 5 wood toothpicks that we bent in the middle and arranged in a star. We then dropped a few drops of water in the middle. As the wood absorbed the water the star opened up. The water is absorbed into the wood fibers due to capillary action which is the ability of a liquid like water to