Numerous universities offer open online courses. Here are two platforms with a wide range of courses:
The New York Times reports about the new partnership between MIT and Harvard. Both universities plan to offer free online courses via the open-source platform edX.
“Harvard’s involvement follows M.I.T.’s announcement in December that it was starting an open online learning project, MITx. Its first course, Circuits and Electronics, began in March, enrolling about 120,000 students, some 10,000 of whom made it through the recent midterm exam. Those who complete the course will get a certificate of mastery and a grade, but no official credit. Similarly, edX courses will offer a certificate but not credit.”
More about edX at MIT news.