In our house we have a recent Peabody graduate and a new Middle Schooler, who spent three years at the Peabody elementary school, and we could not be happier with their school experience. Both have been challenged academically, have gotten a broad education, and have enjoyed themselves. Peabody teachers are truly phenomenal. For them teaching is a calling, and they are deeply committed to their students. They know them well -- their strengths and weaknesses -- and are working on helping to develop them into fun-loving but more mature individuals. Great foundation in all respects. The administration has been coming a long way: lots of creativity and new ideas are being implemented. They are also able to hire and retain the amazing teachers the school has.
We consider ourselves lucky to have found the school. Incidentally, our older has been superbly prepared for high school, without sacrificing week-ends (though he did work hard during the week at Peabody).
We highly recommend the school. While it may not be for everyone, try it out and see whether your child enjoys the atmosphere.
The homework assignments progress steadily over the years. Mostly no homework on Fridays, which is great. Middle schoolers have longer term projects which teach them to schedule and manage time effectively.
The school models these values and pays attention to students following them as well.
Of course, not everyone is perfect but they are certainly striving to do their best. The adviser program in middle school is one example as are the Big Sister and Brothers' programs.