I posted this in the member profile area in response to someone but realize that many people who may find this interesting dont have access to that section. This is the net impact guide to business schools. For those who dont know, Net Impact is a group common across many MBA programs (some have different names but are related). It is all about people using business (your mba) to improve the world. While it may seem to be directed towards nonprofits, net impact is one of the more popular student groups at many schools. I wouldnt really worry about the rankings (you will notice lots of schools you probably never heard of) but reading the specifics of each program can be pretty helpful with determining schools you may be interested in and also with applying to schools.
If you have any interest in social enterprise, sustainability, corporate social responsibility, or pretty much any do-gooder thing...you should read this.
https://www.netimpact.org/associations/4342/files/2007_Guide_For_Download.pdf