I'm a mom with elementary school aged kids, and I have several girlfriends who are teachers with kids. I work 3 12's (6-6), and am home by 630 those nights. The other 4 days, I'm there them completely.
My girlfriends who are teachers rarely leave their class before 6pm(and that's 5 days a week, not 3), and if they do they are taking a ton of work home with them. They also end up spending most weekends working, either re-doing the class, creating lessons, or grading.
Hour for hour, I have way more time with my kids, and work way less.
edited to add: i forgot to say though, the guaranteed weekends, holidays, and summers as a teacher are pretty amazing.