My first year of teaching was absolutely the worst year of my life. The only reason I went back for my second was that I had gone to college on a teaching scholarship and unless I completed four years of teaching, I had to pay back a lot of money. Fortunately for me, my second year was a lot better than my first, and by the time I completed the required four years, I could not imagine myself doing anything else.

During the thirty years that I taught high school, I served as mentor to a lot of beginning teachers, both officially and unofficially, and although no two of the teachers I...