Best of all, the cups help students develop important non-cognitive (or character) traits/skills such as self-determination and collaboration. At first, for example, some students are quicker than others to give up and reach for a red cup. But more often than not, one (or more) of their fellow group members will protest: "Hey, change that back to green." Over time, this I'm-not-ready-to-give-up-and-ask-the-teacher mentality becomes contagious, and students are more persistent. They're also more motivated to reach out to each other for help. Who would have thought a couple of plastic cups could inspire such tenacity and teamwork?