At age 39, I decided to go back to college and become certified as a teacher, knowing well that my income would not be near the same. The two years it took were well worth it. Heck, I was taking some core courses on freshman and sophomore levels so guess who was in my classes?!!
Now I teach in an alternative school with two other teachers with a maximum enrollment of 60 students (we seldom reach that). I enjoy the work in such a way that I do not think of it as a job, but then I've always done volunteer work with youths (soccer, Big Brothers, etc.).
As for the free time, yes, I get 2 1/2 months in the summer, two weeks at Xmas, one week of spring break, two personal days per contract year, nine sick days, and three days at Thanksgiving. I have weekends off (oilfied was 24/7/31) so I have plenty of time to pursue those things I want to do which is to paddle, camp and travel.
Yes, I make about one third less than I did before, but I work one third less than I did before. Plus, I still do the same things that I did before. I have no desire to work in the summer. My situation is different from most in that I am single with no obligations (read that children).
But when you get down to it, it's all about the quality of life and money doesn't always guarantee that.