Happy to report that last December we both successfully completed the Coursera course from the University of Pennsylvania, "Design: Creation of Artifacts in Society". We attained 96% and 97% overall grades and both agree that it was an enjoyable experience.
There were few technical hitches during the course, the lecture videos were of high quality and always seemed to load ok. There were some problems with the peer review process but our grades indicate these were ironed out.
Unfortunately I had to cancel my enrollment in the physics course, "How Things Work" as the start date has been put back to March which is not suitable for me.
I'd highly recommend a Coursera course and I'll certainly be looking to take another in the future.
