Coursera is somewhat different from both edX and Udacity. Unlike Udacity, but like edX, it's a non-profit. edX has been building out its partners, but Coursera already has more courses and partner universities than the other two.
The course list does have a bias towards math/science/tech, I think, but they have a lot more non-math and non-science than does edX (Udacity, of course, has a heavy math/tech bias).
I tried a couple Coursera courses for a few weeks, but like with MITx/edX, I had to drop them. The problem I've had with the edX/Coursera setup is that there are still specified deadlines, and there's not a lot of wiggle room there. I understand why they'd want to do that, but for adult learners who are doing this for enrichment purposes, having courses starting on specific dates and progressing through them week-by-week really doesn't harness the power of the internet and the desire to have on-demand content.
Everybody is learning as they go in this new approach to online education, and I imagine they'll knock out the kinks. I seen that, perhaps in competing against Udacity, some courses have been made more "bite-sized" – running only 5 weeks as opposed to a more semester-like 15 weeks.
I see they've already improved their website in a year, and I see they're hiring more to help on the tech side as well as people to improve learning so I imagine Coursera will improve even more as time goes on.
All 12 Days:
- The Gift of Tongues - free foreign language instruction online
- Learn Lots about History with Bob - long-running podcast on history
- Learn with Udacity - free online college classes, mainly in comp sci
- KHAAAAAAAAAN - free math videos and exercises at Khan Academy
- MIT education for free - online, of course
- Lectures on CD/DVD - with a few of my favorite instructors and courses (not free, but available at many libraries)
- YouTube - not just good for cute cat videos
- Helping those who can't read - cheap audiobook resources for those who need the help, and great volunteer opportunity for those who can help
- Free audiobooks for all! - public domain works easily downloaded
- More free college courses - online, with loads of subjects covered
- Learn to code - online, for free, in a fun way
- The Museum of Math! Woot! (I still need to go in person – maybe later this month)


