Colleges around the country should be worried. The quality of online courses is catching up fast. Depending on whom you talk to, massively open online courses (MOOCs) will upend and democratize higher education, or are half-baked approximations of lectures that can never equal the classroom. Kevin Carey, the director of the Education Policy Program at the New America Foundation put it to the test, spending four months taking two MOOCs, from start to finish. One, a Coursera Introduction to Philosophy was everything critics dislike, he says. Too brief, and with none of the problem sets, essays, or tests that make...