This is an activity that I created for my students to find the mistake when a student has answered questions from graphs about measures of center and variation incorrectly. I used common errors to help them see the mistakes commonly made. All of my products are common core aligned.
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 needed. It was terrific to see the discussions that were going on! This really worked well!