I taught middle school social studies (U.S. history) for a decade. I finally figured out why it was so difficult. I only taught half time, so I only had 90 new names to memorize each year. On the other hand, there are 30 pairs of eyes each period, trained on you at all times, expectantly. You needed to pay constant attention. I know of few other white collar jobs that require that much complete situational awareness.

Teaching is hereditary. My mom taught what the faculty at the time called "dummy English." She loved it because, a decade earlier, that was her. "Helps to have empathy," she said. She gave me several warnings/pieces of advice.

• Don't teach English, too many papers to grade.
• Take one day off each weekend.
• The principal makes the weather; never stay with a bad principal. I knew mine was good when he said to me, on my first day, that I was “teaching in Educational Disneyland,” in a suburban district where the median home price was $170,000.
• Whatever you do, on the first day, do not listen to the warnings issued in the faculty lounge about troublesome students (not kids; kids are goats). Once or twice in a decade of teaching, I dropped by. And discovered almost all the “troublemakers” were boys. And that almost none of them made trouble for me. Was it because I was one of the 10% of the faculty that was male? Who knows?