There are only hairline differences between the middle schools in the Newton community, as they are all terrific institutions in their own right. That said, I tend to read more "We're doing great!" style articles about Brown and Bigelow.
Student to teacher ratios at both schools are about 11.5 : 1, and both schools scored in the top 25 schools in state for the combined MCAS scores. Source: http://www.schooldigger.com/go/MA/schoolrank.aspx?pagetype=t
If you have any other questions, or would like assistance with your housing search, don't hesitate to contact me directly!
You can also check the website http://WWW.GREATSCHOOLS.ORG which is a bit more subjective and ranks them in the order of Bigelow, Brown, Oak Hill, Day.
So seems to me if you stick to Brown and Bigelow, you are in good shape. If you need any help finding a home here, just let me know. I would be glad to help.
A great place to look at what makes each school great is http://www.greatschools.org as well as taking a look at the school profiles on http://profiles.doe.mass.edu/mcas/performance_level.aspx?lin
Our Middle Schools are Bigelow, Brown, Day and Oak Hill ... let me know if I can be of any more assistance. I do work for renters.