The overhead projector is perhaps passing out of use, but it is still a useful device with which to do lecture demonstrations. In my early years at Kenyon I was teaching the pre-med course, and found that the overhead projector was an ideal platform for showing the phenomena of polarized light. This note is a discussion of how I learned to use the projector for these demonstrations. Now that I am in my eighth decade, I would like to pass on some of my earlier teaching techniques to my younger colleagues.