For this activity, students must first be familiar with exam free response scoring rubrics. (I teach AP Computer Science A, which has plenty of resources available online for free response rubrics and scored samples.) When students have seen the rubrics enough to know how to earn partial credit on questions that would otherwise seem to difficult to approach, I turn it up the rigor: students work in groups to write their own rubrics and canonical solutions. The extra tasks turns familiarity into mastery.
How is it implemented?
The first is deciding on the point breakdown: which part of the question is worth the most points? This is the most fundamental question because it teaches students where they need to put their own focus while taking an exam. In the 2016 Computer Science A exam, question 2 (which is worth nine point total) part (b) is far more challenging that part (c), but part (b) is worth 2 points and part (c) is worth 5 points! Knowing where the emphasis is placed helps students make effective use of their exam time.
After distributing the nine points, the next task is determining how the work earns points. This helps students explicitly break a problem into steps, where each step has a point value. This phase is especially helpful for students who may have been entirely stumped by the question when they attempted it on their own. Working in groups, the students discuss how the problem can be simplified and broken down.
It takes 45 minutes to independently answer two free response questions. It take another 45 minutes to work in a group to devise a "canonical solution" to a single free response question, write the rubric that goes with it, and leave time for discussion.
The groups are self selected.
Why do I like this activity?
This is a prominently student-centered activity that fosters rich discussion and results in a high payout for learners of varying levels. It is far more engaging than going over the answers as a class and from conversations with students, most if not all of their questions are answered by their groups during the group work.
As we get ready for end-of-year exams, I am brainstorming review activities and writing about them in this series, "Work Smarter, Not Harder" (Read Ex 1). If you've got one you'd like to share, please let me know in a comment.