that may well be, but i NEVER used a multi choice exam but once! i assigned them generic questions for each weeks reading assignment, which i read, and always gave essay exams.
i know there's a steep learning curve and that you can spend a great deal of time on teaching. but, you don't *have* to. my student load was anywhere from 20-50 students, too. in the case of large classes, i did cut way back on what i did. i also had the "luxury" of teaching two intro classes back to back at colgate. my point was that, considering the amt of time one needs to spend, even at a high ball of 15 hrs per week for, say, 30 students for a 16 wk semester, your hourly wage is far better than that of a housekeeper or janitor. when i taught four courses per semester, i spent 50 hours per week working, on avg. for 16 wks and made 12,400.
that's a burn out schedule. so pull it back down to, say, 8700 for 16 wks. plus teaching 2 courses in the summer for 2200 a pop. that's 21,800 a year. STILL considerably more than a housekeeper -- and you STILL have ~ 6-10 wks off for the year! (i'm counting a couple of wks prep time and grading time even!!!)
again, it still sucks compared to the 40-75k fulltime fac tenured fac work for the minimum of say 40 wks per year, but it's better than housekeepers and janitors!