Melting crayons in the heat not only makes for a great art project, but can also be a neat science experiment to do with the kids. The experiment shows how dark colors absorb more heat than lighter colors. As a result the darker colors melt before the lighter colors, like white. This is why the dark pavement is so much hotter than the grass. Black has a low albedo but absorbs the heat pretty easily. While the “color” white reflects light very easily.
All you need to do the experiment is a piece of poster board, Crayola crayons, tape, or a hot glue gun. We tried the experiment with the wrappers off, but the crayons wound up falling off, but when we kept the wrappers on they stayed in place, but it took longer for the crayons to melt. We also used tape, but a hot glue gun will work better.
Line up the crayons from dark to light and wrap them in tape, then tape them to the poster. Set the poster in direct sunlight around 12pm or 1pm when the sun angle is high. Let it sit for a couple hours, and the crayons will start to melt. I’ve heard that Crayola works best. I would check your project after 30 minutes, as some crayons will melt quicker than others depending on if the wrapper is on, and the air temperature.
Put another piece of cardboard on the bottom, so you don’t make a mess on the ground. Be prepared for it to be somewhat messy. You’ll want to do the experiment in clothes you don’t mind getting stained. Send your final projects to aschilling@ktvn.com, and if I have time I’ll share them on air.