I go over the entire in-class exam generally the period after they take it. I tell them how many points I took off for each mistake. I also try to relate how the problem relates to similar questions from class. If a large number of students make the same mistake, I bring that to their attention. I am of several minds about showing students the score distributions. I know I always look at a stem plot of the scores. I sometimes share with students a stem plot of the scores, but I do not show scores below 70 - I don't want students to be able to know their neighbor got the lowest score. I do like the idea of showing students that some of their peers scored very well on the exam. I put the total score for the test on the second page of the exam to allow students to retain their privacy if they wish. I do not give them access to the exam key generally. I do write comments on the exams. I try to circle the mistake. I don't give the correct answer on the exam. I also indicate how many points I took off for that mistake. I consider students losing points for mistakes. I've considered adopting a more holistic approach - using a scale from 0 to 4 for the question. I have yet to try such a thing. It would certainly allow me to worry less about taking off exactly the same amount of points on each exam for similar mistakes. Some mistakes are not similar from student to student and grading those mistakes eats up more time.

I return the take-home midterm after about a week. Since each student thinks their data is unique, I do not go over the exam in class. Students do not have the opportunity to resubmit their take homes for a higher grade. I do more writing on the take home exams to explain mistakes. I have a rubric that I use to grade these and students do see their score on the rubric. If many in the class made a similar mistake (like failing to provide an adequate introduction), I will announce that to the class. I write "see me" on a part of the exam where a mistake is difficult to explain in a short sentence. Students who do poorly on the take-home, I write "see me" next to their score to encourage them to see me so that we can find out what went wrong in the completion of the take home exam.