I have been running photography courses now since around 2008.
One of the longest running courses is Photoclub in the Pub, a 6 month long creative photography course with 5 creative assignments. We meet once a month in the pub to discuss each assignment and do a slideshow of everyone's images. Photoclub in the Pub also has other benefits such as reduced prices on other courses, prints of your images and video screencast feedback on your images.
Photoclub is been really successful for us but we were finding that some people wanted some of the action but couldn't get to the pub meetings, either because they were not local or just busy on that night. This is when we came up with the idea of the online version of Photoclub in the Pub which we call Creative Assignments.