Funny you say that because I'm an Army officer, so people regularly thank me for my service, but my wife arguably worked harder, had more responsibility, and was contributing more to society while she was in those schools. And she got paid less than a 19 year-old private in the Army. In fact, the principal of the whole school was paid less than I had been paid as a lieutenant in my early 20s.

Anyway, what's hard about teaching is not pedagogy or the subject material itself, but rather the administrative burdens and management of large and diverse classrooms, as you said, unfortunately.