Teachers do not always escape long work weeks.
One of the reasons I went into teaching was because I wished to avoid "60-80 hr weeks." I reasoned that I could make up for the low salary by playing poker on the side (I was a pro poker player prior to being a teacher). This has not worked out for me.
I am a teacher at a private school in the USA. Part of my duties involve coaching in the fall and winter. This means that in the winter and fall I am at school from 7:30am-6:00pm every Monday-Friday, and about 1:00pm-5pm every Saturday (only in the fall). It is important to note that these are all required hours; I must be at school for those hours. This does not count any of the work I do at home (grading, preparation, etc). I can get some grading, extra help, and prep done at school, but not all of it. I generally always have at least 30 minutes of work each night and a couple hours on Sunday.
When progress reports are due, the workload increases dramatically. On top of all of my other responsibilities, I must also submit grades and write individual reports for 55 students.
In other words, I have not had much time for poker.
Of course, the long vacations are nice, but the salary is not. I expect to work longer hours as a quant, but I also expect to paid MUCH more. I also expect to be rewarded based on merit.
The final straw came when I started considering switching to a public school so that I could avoid coaching responsibilities. So, I started looking into getting a masters degree so I could move up on the pay scale. However, as I pondered taking graduate education classes, mind-melting nightmares from insipid and vacuous undergrad courses with titles like "Social Foundations of Education" and "Adolescent Psychology" came searing into my mind. No thanks!
Because of this, I am currently applying to a handful of FE/Math Finance programs in the area and keeping my fingers crossed.
If you are ok with a low salary that only creeps upwards because you stuck around for another year, and you like kids, then go for it. I like teaching, but I can't take care of a family with the salary, so I have to do something else.