I recently completed the Microeconomics Principles MOOC, offered through Coursera by the University of Illinois at Urbana-Champaign. Something like 37,000 people initially signed up for the course–about the total number of undergrads at UIUC. But only about 1% of those who signed up participated in the course’s weekly discussion forums at all, and the number of forum postings diminished steadily over the course’s eight weeks. By the end, it seemed like an Econ 101 class at a small liberal arts college.