The Harvard University Extension School run a series of Environmental Studies courses, including Planning for Carbon Neutrality: Practical Methods for Developing and Implementing Greenhouse Gas Reduction Plans (E116). The offer a Graduate Program in Sustainability and Environmental Management and the Sustainability Certificate.
E116 has assignments where the student has to estimate their Personal Carbon Footprint , prepare a Greenhouse Gas (GHG) Inventory, and Critical Review of a Published GHG Reduction Plan. The course has an Online option (but it is not clear how the on-line courses are provided). Interestingly, the courses are comparable in cost (undergraduate $AU1,025, graduate $AU1,950) to Australian courses, such as ICT Sustainability (COMP7310), which I run for ANU.