I have just started my fourth MOOC and I love every minute of it. A MOOC is a massive open on-line course. They are free and run by some of the top universities in the world I have just started studying Ancient Greek at Harvard. Before that I did Philosophy and Digital Education with Edinburgh University. I am also half way through Modern and Post Modern at Wesleyan University.
There are a number of places you can find information about MOOCs. For the first two I used Coursera.org and for the most recent I used the Harvard direct link.
The professors are enthusiastic and inspiring.
On my philosophy course there were over 90,000 students in my class. The lectures are on line using video that you can watch when you like. There are course notes and reading lists. Each course is slightly different. For some there are tests at the end of each week, for others you need to submit work for peer review. There is limited contact with the course professor obviously as dealing with such huge classes they can't answer all the question. You can generally get an answer from your peers on the forums.
If you feel you have gaps in your knowledge on any subject the take a MOOC.
Right back to The Iliad.....