We have to sign in before 8.30 AM and sign out after 4.30, so nominally work a 40 hour week. The actual hours of work we do can vary from a few less to quite a few more.
As a teacher at a university for the hoi polloi in a partially developed country, I am contracted to do 18 contact hours per week, and have had 150 - 250 students on my rolls. Being fairly diligent, each contact hour can involve an hour or two or more of non contact time.
Like most of my colleagues, I spend very little time in our dreary artificially lit, air-conditioned office on campus. I prefer do my preparation and marking in my apartment, with good natural light and airflow, about five minutes away by bicycle.
That used to be my life, too. And, for a very long time, I loved it. Re teaching, it varied - sometimes, relatively non-stressed, sometimes incredibly intense and very demanding of your time.
As a teacher, I found that you could multiply the contact hours by the time taken to prepare classes; classes that I had taught earlier, often the more basic courses taught to say, first years, would often require an additional hour (maybe two) of contact time. My own specialist courses were different - and usually taught to final year students. Then, I would average around four-five hours of preparation per hour taught.
Summers were mad, in that you spent weeks correcting scripts and exams, morning, noon, and night, barely surfacing; those were 12-14-16 hour days, as strict deadlines applied before the exam board meetings.
Latterly, I work in a somewhat different field, and again, it largely depends on deadlines. Reports need to be written, and sometimes, the deadlines approach with unnerving speed as situations on the ground change with alarming fluidity, meaning you remain at your desk until everything is completed. At the moment, in theory, I am working a 44-48 hour week, but flexibility is required, and sometimes, one ends up putting in many more hours than one had anticipated.
For what it's worth...I have the greatest respect for teachers.
I know the hours suck, and the pay usually sucks worse...but you are doing important work.
True, the pay wasn't great when I worked as a teacher, but, at its best, few types of work offer such job satisfaction. I used to love going to work, which compensated for a lot else; in addition, as a university teacher, I had considerable autonomy over what I did, and how I did it, an autonomy I realised mattered enormously to me.