I am constantly amazed by how well my high school students respond to activities that at first glance seem too juvenile or too childish. Find someone who was an activity that seemed stilted and artificial at first glance, but worked really well in practice. To play, you need to find someone who can answer the questions on your worksheet/playing card. It's normally used as an icebreaker, or a sort of human bingo game, but it can also be a collaborative learning tool.
Today my tenth grade chemistry students learned about ions, and I wanted to reinforce the lesson by having them practice naming ionic compounds. The lecture was going ok, but not great. About half the class was engaged and asking questions, but the other half was completely out to lunch already. Eyes glazed, heads drooping, and I felt like cold calling was only going to make them surly.
So I gave them a table of polyatomic ions and a list of ionic compound formulas. All they had to do was find someone else in the class who could name one or two, and write down the answer with their initials. All of a sudden, everyone was standing, interacting, and collaborating to name these ionic compounds. Students knew they had to get everyone's initials, and they didn't want their own initials to appear next to an incorrect response.
If I had just handed out the worksheet for them to complete at their seat, they might have started a few but I have a feeling they would have started chatting about things other than chemistry and by the time the bell rang they might only have twelve of the 24 finished. By playing find someone who, they had to check each other's work and reinforce their comprehension AND we had time to check against a key before the end of class. WIN.
Here is our document for find someone who.