Academic Earth
Academic Earth is a website that offers free online classes and online learning tools. Academic Earth can also introduce you to universities that match your interests.
Alison.com
This is another free education service online. Alison.com offers free college-level courses for basic workforce-related skills.
Corsera
Take courses in a wide range of topics, spanning the Humanities, Medicine, Biology, Social Sciences, Mathematics, Business, Computer Science, and many others. Video content comes from many different universities with some offering certificates for completion.
edX
edXfounded by the Massachusetts Institute of Technology and Harvard University, provides free college courses from 27 of some of the top universities around the world.
KhanAcademy
This site provides free 10-minute instructive videos including K-12 Mathematics, sciences, and humanities subjects.
Learner.org
Annenberg Learner provides free videos for teacher advancement and classroom resources to help develop teacher abilities.
Merlot
The Multimedia Education Resource for Learning and Online Teaching is a free online resource for teachers and students to share educational and pedagogical resources with other students and teachers.
MIT Open Course
The Massachusetts Institute of Technology publishes course materials from almost all of their courses free online for public use.
Open Culture
A comprehensive, cultural and educational media site. Contains audiobooks, ebooks, online courses, movies and other collected content.
Saylor.org
Take college classes online for free with this collection of college-level courses developed by a group of college professors. After each completed course you earn a certificate acknowledging that you completed it.
Ted Talks
Ted Talks is a collection of videos from their conferences presenting "Ideas worth spreading." Each TED talk, 18 minutes in length, presents some innovative idea.