Free online classes:
Udacity.com : The best free online courses I’ve found! Though they only have a couple dozen courses so far.
MIT Open Course Ware : The behemoth! I haven’t used it yet, but its MIT.
Learnstreet.com : Not as good as Codeacademy.com, but a good supplement and free.
Udemy.com : Some free, some paid. I wouldn’t recommend paying for anything because courses may be hit or miss. Browse the free ones though, there is a multitude.
Coursera.com: Offers a wide range of free courses with a start date and end date. Advantage: Other people are taking the course with you and you can discuss the material with them! Disadvantages: You can’t progress at your own pace.
Khan Academy: The original free online school! Khan Academy has a ton of great youtube videos and a number of excellent interactive elements for a range of subjects. If you are learning math, this is the place.
Educational Youtube channels:
RSA: Educational videos presenting new innovative ideas in a fun, captivating way including animation!
Crash Course: One educator with his team makes “crash courses” on subjects from History, to Chemistry to Literature. They are fun and packed with information.
Periodic Videos: A charming mad-scientist looking fellow shares his love for chemistry with the world on these informative and entertaining videos.
TED: The New York Times of youtube lecture series.
Edge.org: A website dedicated to spreading new ideas by getting smart, cutting edge thinkers to talk about what they are doing.