The school does a decent job of differentiating, but mostly in math. In the lower grades, they do a good job in reading as well. In my experience, a lot depends on the teacher, and how much he or she is willing to put into differentiating for the students.
The homework load is generally very reasonable, and it is rare that the kids bring home anything that I would consider busy work. It is either work meant to reinforce what they have learned in school, work that they were unable to finish in school, or work that I feel is generally useful. Since Mirman has instituted flex time most days, my kids' homework load has dropped significantly.
We have been at Mirman for 8 years, and have never had a bad year there. There has been a lot of turnover with teachers since the new headmaster arrived, and while, the thought of so much change has been scary, the children don't seem to notice, and the changes, for the most part, have been overwhelmingly positive. Our children are excited to go to school every day, and have their love of learning stoked by amazing, dedicated teachers. It's a wonderful place for parents as well, as the families at Mirman, while diverse, all have the same end goal in mind, which is to cultivate in our children a curiosity and love of learning that will last long past their days at Mirman.
Dan Vorenberg, Mirman's Head of School, feels passionately that children's social/emotional development is just as important as their academic development. He has implemented a variety of programs and emphasizes a culture of respect, compassion and integrity.
Upper school teachers in particular are truly fantastic. They are more like college professors. The level of instruction in lower school varies, depending on what teacher your child gets, but for the most part they are skilled and effective.
Homework is reasonable and not busy work. The amount given is supposed to correspond to grade level as follows: 10 minutes for K, 20 minutes for 1st grade, 30 minutes for 3rd grade, and so on. In lower school there is no homework on weekends.