My mother taught for 35+ years in Indiana. My wife taught for 3 in inner-city schools (Houston then Chicago). I'm well aware of how much teachers work outside of school. It's not as much as they complain about.
https://nces.ed.gov/programs/statereform/tab5_14.asp
Most school days are 7 hours long (approx. 8-3). Let's assume teachers are working that entire time (they aren't): that's 1,260 hours a year spent doing their job. Compare that to someone who works 9-5 throughout the year, with a month total of time off (VERY generous). That comes out to 1920 hours a year. Compare that to an entry level lawyer at a medium to small sized firm, who might make about 60-70k, but has to BILL 2,000 hours a year (lawyers cannot and do not bill close to all the time they spend working). And I haven't even brought in the benefit package a teacher gets (in Illinois, an amazing pension, great health care).
So, on average, I think it is hard to say teachers are over-worked and underpaid, especially given the actual results they are achieving.