In August 2014, more than 300,000 people registered for the first offering of the Introduction to Linux course. This popular Massive Open Online Course (MOCC) is taught by the Linux Foundation, and hosted on edx. The same course starts again on January 5, 2015.
The course is designed for people who have limited or no previous exposure to Linux. Despite that, I have enrolled in it, thinking that I will pick up some new knowledge anyway. Because it is self-paced (and free), if it proves to be too easy, I will just skip the course content.
If you are interested, please go enroll at edx today.