Make 'em work to get their test back

Back in November, I gave my freshmen a test consisting of ten"justify your answer" questions.  They did fine, generally, but I became frustrated when they did corrections.  They focused so much on figuring out why they lost points, on what they did wrong to begin with, that they couldn't redo the problems right.  In that previous post, I suggested that next time, the students would get back merely a blank copy of the test with the problems they missed circled.  Sure enough, I did exactly that last week.  It worked well, even though it was a painful 30 minute process to go through the blank tests to circle the problems that had to be redone. 

In this process, I stumbled into a couple of good teaching ideas that I'll share.

(1) David McRae, our math department chairman, caught me in the act of preparing the blank tests.  He told me of a presentation he saw at a math conference: a professor graded tests by writing detailed commentary, without writing anything at all about points gained or lost.  He tabulated grades separately, and did not (immediately) share the grades with the students.

We all know that students tend to look at their score and tune out if we don't manage the turnback of tests very carefully.  This professor took that principle to the extreme -- without scores available at all, the students could do nothing but read commentary to figure out what they did wrong.  David says he has tried this approach in his advanced courses, to very good effect (though it takes ~4 times as long to grade).  While this wasn't my approach, it's similar and interesting -- I thought I'd share.

(2) When I presented students with a blank test to correct, I did so for physics teaching reasons.  When confronted with their graded tests, students were so prejudiced by their previous responses that they had trouble redoing the problems without making the same mistakes.  The experiment bore out my hypothesis that the blank test would solve this issue.

What I hadn't counted on was the psychological effect of not returning the graded tests right away.  Many students asked, "Can I just see my original test real quick?"  They were noticeably antsy, like a Starbucks addict consigned to drink weak-sauce hotel coffee.  Test grades are a drug -- our students have been conditioned to work for them, live for them, measure a bit of their self-worth by them.  

So without any premeditated intent, I had created an amazing incentive for good test corrections.  I was holding their tests hostage!  The ransom cost: doing the problems they missed correctly.  You should have seen the relieved looks on their faces when their last corrections were approved, and they could have their tests back.  Even those who didn't do particularly well felt fine -- they now knew how to properly do every problem, which dulled the sting of a D.  They were less inclined to sour grapes ("Woah, that test was just really hard, nobody should be expected to do that.") and more into self reflection ("D'oh, I really knew how to do a bunch of those problems I missed, so I should have had a B+.")

GCJ