It works like this. I had the kids draw a clock on their paper that looked like this.
I then had the entire class stand up and told them they would have 2 minutes to make 4 appointments. They needed to make a 12, 3, 6, and 9 o'clock appointment. They could not book the same person twice and they were to sit down as soon as they made all four appointments so I would know who was finished. In each class there were several who still needed appointments after everyone else was finished, so I just told them I'd place them with a group for the appointment that they were blank on.
After their appointments were made, their clock looked like this.
After everyone was seated, I instructed the students to go and meet their 3:00 appointment and work problems 1-8 on the test review. They could work anywhere inside the room. Most just pushed desks together and worked like this.
After about 10 minutes, I called time and told the students to meet their 9:00 appointment to do problems 9-18. We continued this process until the reivew was either finished or we ran out of time. The kids had a blast and asked if we could do it again sometime. I really enjoyed seeing the 100% engagement and most of the students were great about helping each other and not just giving answers.