This is a very good way to have students analyze mistakes which creates a better understanding of the concept. I created this for my students to find the mistake in problems "a student" had solved incorrectly. I used common errors when creating the solutions to help them see the mistakes that are commonly made.
I had the students work alone to solve the problems first, and then share with their groups. If there was any discrepancy, they looked in the answer folder on their tables to see the correct answer. I rotated around monitoring and helping as individuals or groups needed help. It was terrific to see the discussions that were going on! This really worked well!