7. Open Learning Institute
The Open Learning Institute from Carnegie Mellon University allows access to a handful of course materials so you can learn at your own pace from the same kind of materials and self-guided assessments that would be used in a classroom. Their offerings are limited, but there’s a lot of detail in the coursework. Instructor-led courses are also sometimes available.
8. Open Culture
This site isn’t very pretty, but Open Culture does boast a collection of more than 700 downloadable courses, including college-level, certificate-bearing classes, language lessons, educational materials for K-12 and more.
There are also just some interesting links that aren’t to courses but you’ll still learn something from, such as this post on a reading list suggested by Ernest Hemingway.