The class of 2012 heads off to school this fall, and some are left wondering if the college they've chosen is Eco Friendly or not. Recently, the Princeton Review added a green rating to its annual ranking of the best colleges. This score measures how environmentally friendly, responsible, and committed the institutions are. Here is a lift of the "green-est" colleges in America.

The schools that scored 99 (out of 100) are:

• Arizona State University, Tempe
• Bates College
• Binghamton University
• College of the Atlantic
• Emory University
• Georgia Institute of Technology
• Harvard University
• University of New Hampshire
• University of Oregon
• University of Washington
• Yale University

What really makes a collge green anway? different organizastaion have differnet crtirea for what makes a collgees green. The independent Sustainable Endowments Institute has published a Green Report Card. The full report is available as a PDF online, and it evaluates 200 public and private universities.

The Green Report Card looks at more than just green buildings and recycling. It asks how the schools are using their substantial endowments to support sustainable efforts and fight climate change.

Overall college sustainability leaders on the report card include:

• Carleton College
• Dartmouth College
• Harvard University
• Middlebury College
• University of Washington
• University of Virginia

There are even more lists like the Daily Green's top 10 colleges, Grist's 15 greenest colleges, the Sierra Club's 10 cool schools, and Campus Corner's greenest college towns. But smaller schools and not-obviously green schools are looking to reduce their carbon footprint too. Over 550 university presidents have signed on to the American College and University Presidents Climate Commitment, which pledges to reduce the carbon footprint from campuses nationwaide. Signatories include Boise State University, Eckerd College, Indiana State University, Temple University, and University of North Texas.