This happened to me as an instructor. My car was broken into and my leather satchel full of student work was taken; some problem sets and homework for other classes, and a set of midterm exams for a second-term calculus class.
Here is what I did. I told my students that I would re-write the exam and they could take it at some point in the next week (at the testing center), and I would score it and grade it just like the syllabus said. If not, I would either figure out the grade by re-scaling everything appropriately, or substitute the final score for the missing exam – whatever was better for the students’ grade. NO ONE chose to retake the exam, but I felt I had to offer it to follow the syllabus structure.
In the end it didn’t seem to matter much for the grades; everyone got about what I thought they would and the grades were in line with other calculus classes I’ve taught. It was personally annoying to have it go missing, however, and it took away some of the performance-evaluative feedback I could give at the half-way point of the term. But as a class we rolled through it.
As an aside, they took that satchel full of exams, and a cigar box underneath full of polyhedra dice. I can only imagine the look of shock and dismay as they realized that they would not be selling anything for meth that day:
-Dude, what’d you get?
-I busted a car window and got this sweet leather bag, and this cigar box with something heavy rattling around!
-Sweet! Open it up!
(Stunned silence as they look at math papers and D&D dice)
-Dude. You robbed a geek.
Author: , Math Teacher at Portland Community College