I taught my first class in 1955 as a graduate student Teaching Fellow in the Harvard Philosophy Department's Introduction to Philosophy, taught by the venerable Raphael Demos [then perhaps fifteen years younger than I am now!] That year, and the next, I was responsible for three discussion sections each semester. I taught my last class two years ago, as a professor emeritus, in the UNC Chapel Hill graduate Public Policy Program. Starting with those discussion sections, each time I taught a class, I would open a manila folder for the class list, the syllabus, any handouts I might produce, and my hand-written record of each student's quizzes, essays, examinations, and class presentations, with little notes to myself about his or her performance and the grade I assigned. Fifty-six years of course folders sit in my file drawers, arranged chronologically. They are a complete record of a lifetime in the classroom.
From time to time, I hear from a former student. A woman whom I taught thirty years ago wants a letter of recommendation. [Yes, that really does happen, and more often than you might imagine.] A man who took my course on Kant's Critique of Pure Reason in 1960, and who is now in his seventies, drops me a line to say that he enjoyed the course. Just last month, a young man who signed up for a course with me in the 1990's but never was able actually to take the course asked me to fill out a retroactive withdrawal form so that he could finally complete his undergraduate degree.
In each such case, a quick trip to my file drawers allows me to recapture exactly what that former student chose as a topic for the final paper or how he or she did on the midterm exam. Somewhat disingenuously, I am prone, when I hear from a student of thirty years ago, to say in my reply, "Of course, you chose to write a critique of the argument in Hume's Third Dialogue, and although I thought you were wrong, I also thought you did a fine job of it." Ah, they think, how can he possibly remember me after all these years!
If you are a graduate student or a young Professor, right now start keeping records of all your courses. I understand that you cannot really imagine still being at this fifty years from now, but trust me, the time will pass, much faster than you might like, and there is a world of pleasure in having ready to hand a record of every young man and woman who passes through your classes. After all, if you had chosen to be a professional baseball player, every one of your times at bat would be recorded somewhere. Surely your students are as important as balls and strikes!