Coursera

This site offers both free and paid courses from colleges and companies. If you take a course in audit mode, you will be able to see most course materials for free. To access graded assignments and to earn a Certificate, you will need to purchase the Certificate experience, during or after your audit. You can even apply for financial aid if you choose to. Every course you look at shows the stats for each person who completed it and how it benefited them. A lot of the courses have sign-up dates due to a time structured lesson plan. Registration is required.