teaching is hard work: a little-known fact about concentration

This semester, for the first time ever, I am teaching classes that are back-to-back. I have fifteen minutes between the two (which boils down to about six minutes of my own time - the end-of-class questions and comments always takes time, and usually the before-class moments involve solving someone's problem as well).  I've taught two classes on the same day before - one morning, one afternoon; once, I only had about an hour and a half between recitations (for the same class).
But fifteen minutes? shoot. that's nothing.

Each class is one hour and fifteen minutes in length. One, Representing Adolescence, is both a class I've taught before, and extremely familiar turf. I know my YA. The other, Myth & Folktale, is brand-new to me. And I am definitely a tourist in Myth & Folktale. But I've been working hard since late October to educate myself, and it's paying off (though next week, we start the ancient Greeks - Hesiod - and the real test begins).

The point of all this schedule talk is: I am exhausted when I leave school.
Why?
Because teaching is hard work.
Teachers, and the children of teachers (of which I am one), know this already.

It wasn't until a couple of summers ago that I realized just why class is so exhausting. I'd been teaching for at least two years by then; it was my third summer of teaching in the six-week intensive schedule (class twice a week, for 3 hours and fifteen minutes each day).
I was watching, on one of the last days, one of the girls fiddling with her phone, texting or checking messages, or something. Discussion was going on, and I was listening, but her phone was in a bright pink case and caught my eye. And in that moment I realized: when I'm teaching, there is NO daydreaming. No doodling. No checking messages. No working on my grocery list, or my To-Do list, or drawing pictures of cats and dinosaurs and bored stick figures while I listen to the professor or a classmate. When I'm teaching, my brain is entirely, entirely focused on the task at hand.

Usually, when we (people) do things, our brain is occupied, but there's room for a bit of multi-tasking. Cleaning and listening to music, for example. You can handily do both. Studying and listening to music, perhaps. I've had a couple of different kinds of jobs, including a Real Job as an Administrative Assistant at a national nonprofit, and I know how unlaserlike my focus was. You work for a bit, check some email, go to the bathroom. Get a drink. Work some more, while an acquaintance makes a face at you as she passes by. Set one task aside for another. Your mind can wander a little. In these here days of uber-connectivity and technology out your ears and twitter and facebook, the distractions are almost infinite.
It's not hard to find studies about this - a google search turned up a massive crop on productivity, distractions, etc. Whether distractions are good or bad, stress-inducing or stress-relieving, isn't the question here. The point is, it's likely that the average desk-job employee spends 20-25% of her workday NOT doing the work she's there to do - in other words, doing personal crap.
So much for "teachers work a shorter day."

See, in the classroom, there are no breaks to check facebook, or email. You can't put off your students, when they're there staring you in the face.

And to teach a discussion class - or even a lecture class - your brain has to be pretty close to 100% tuned in to what you're doing. You can't gaze out the window and drift away for a few seconds while a student is asking you a question. You have to be ON the whole time.
At first, I thought the tiring-ness of this was because I was new to teaching. But my parents - lifelong public school teachers, now retired - both said "nope. that never changes." It's always tiring, because the concentration required to maintain your class is tremendous.
And because every class is made up of different students, even if I'm teaching the same book for a second semester, it never becomes automatic or mechanized. There's never a point where I can detach my brain a little from what I'm doing, or saying. When the students talk, I need to be listening - and not just paying attention. I need to be processing their words and thinking as they speak how to respond. It's a little like the focus you need in a job interview - you cannot just start woolgathering while the HR person and the CEO ask you what you'll bring to the team.
So my three hours of teaching is three solid hours of work. Not 80, or 75% of three hours. It's every minute of that time.

Grading works the same way - you cannot actually grade writing and let your mind wander. So every minute of grading is a full minute devoted, not just 40 seconds. If my mind starts wandering, I have to stop work. You cannot effectively grade an essay if you've read six sentences with no idea of what you've actually read. there's no toggling back and forth. There's procrastination, of course, and the nice thing about grading is that you do that on your time frame (for instance, I don't have to show up anywhere at 8am to begin grading, and stay there until 5pm). I can start grading at 10pm and work until midnight. But those two hours? those are two solid hours of work.

One of the complaints, or criticisms, or snarks, leveled at teachers is "you don't work a full day" and "you get summers off."
The actual school day may be less than 8 hours, though many public schools require teachers to arrive well in advance of the students' arrival and the start time, so it's quite possible to spend close to 8 hours in the building. And you get a lunch break, and a work period (in which, as far as I can tell, most teachers spend their time doing work - grading, prepping, etc - and not checking facebook). But then you go home. And your bag is full of essays to read, tests to grade, texts to re-read for tomorrow, lessons to plan.
And again, a lot of that time - all the in-class time, and all the grading of writing - demands all of your focus and attention.
It's exhausting. It's draining.
But it's also, often, completely exhilarating - at least the classroom part is, at least for me - and that's what makes it worth while.