I live in a neighboring town. It's relatively quiet - even the main roads through these small 495 towns generally aren't a distraction, and things are more or less peaceful, quiet, and pretty chill.

No input on the Mendon schools (I don't have kids in school), but as others have mentioned, having a zoo nearby is pretty sweet. It's not a world-class zoo by any means, but it's an awesome way to spend the day a couple times a year. For adults and for kids. I'm a grown ass adult, and when my parents drove up to stay with me for the weekend, we went to the zoo. We had a great time.

If the kids are outdoorsy, this neck of the woods is much better than most places inside 95. There are so many trails, parks, ponds, etc.

And Mendon has one of the few drive-ins left. If the kids are restless to the point that going to a movie theater isn't ideal, the drive-in could be pretty sweet. There's always people wandering about when it's warm before the movie (tailgating, throwing a frisbee, people-watching, going to the concession stand, etc)

Another comment mentions the traffic in Framingham. 495 is nothing compared to 95 most days. The stretch of 495 from about Milford to the Pike can get slow, but rarely as bad as 128 gets. If your work hours are even an hour out of "the norm", you'll be fine - not a lick of traffic. And I guess you could take 16 into Holliston and then 126 North into Framingham. Surface roads, but at least it'll be moving.