This was an after school program that I put on for kids at my library. I've been seeing this STEM activity floating around the internet for a while now. And I'm SO glad we finally did it here at our library! It was a hit with our after school crowd. I initially used the idea from this blog and the instructions found here. But, of course, I did some of my own tweaks so here's my little tutorial... Here are the basic materials that I collected for attendees. Every kid got one plastic cup, one…