Yesterday, I taught my very first science class for “big kids.” This summer, I get to teach an hour long class for children about to enter 1st grade, and another hour for children about to enter 2nd, 3rd, and 4th grades. Yesterday’s theme was the power of light. First, we found natural materials to make our initials on sun sensitive fabric squares and put them out in the sun. The fabric is coated with a chemical that reacts to UV light, so the part that you cover up will turn out a different color than the part you expose to the sun. While we waited for this change to occur, we used UV color change beads to make necklaces. These beads all look white while inside, but when you take them into the sun they change into a rainbow of beads. I challenged the older children to try and make a pattern with the beads (there is just a tiny hint of difference in the colors when you’re inside), and when we took them outside, we would see if their pattern worked. One of the girls got a three-color pattern to last for three turns! I gave her a 20¢ coin from Swaziland as a prize. At the end of class, we used glow-in-the-dark paint, liquid starch, and Elmer’s glue to make silly putty that glows. Everyone got a squeeze of paint in a bowl & about 1/2 cup of liquid starch. They mixed it together with their fingers & then we added about 1/2 cup of glue, mixed some more, and ended up with really cool glow-in-the-dark silly putty. By this time, our sun print fabric was done outside, so we brought it in and rinsed it out, then lay it flat to dry. It was an exhausting and fun science hour, both hours of it!