Update: I tried this Powerpoint out with my middle schoolers today, on 3/16/16 (beginning of the academic year, here in Korea) and they really enjoyed it. Some of the teams would get the correct answers while others hopelessly floundered. There were some students who said "more more," after reach consecutive round because they wanted to continue playing despite my wanting to move on to other activities.
We used the white boards to have each team show their answers.
This ppt took longer than I expected, about 20 minutes (I gave the students time to think about what they had to write).
I would recommend this to other teachers, so far.