I worked as a TA in a university. There are people there also, missing deadlines and asking for higher grades. They just don't do it in front of everyone.
There is a simple solution to this problem:
- Clear, written rules for all, posted at the beginning of the course
- Enforcing those rules on forums too (people will cry, but let 'em)
- Deadlines, that give time to finish the assignments
- Deadlines, that do not move, even if they are bombing your city
I have encountered many of the same problems myself, taking MOOCs. They go away, when the instructors learn from these things and create new rules, and enforce them. This is how Coursera is evolving. The student material is the same, but the instructors learn from their previous problems with the students.
I've also noticed, that the quality of the forums is often based on a few bright inviduals , that really bring insights into conversations (and one of them was from India, and he was a better programmer than me (15 years of experience)). If everybody is a nagging idiot, well the forums are not going to be fun. That is the price we pay for free education without prequisities.
I am actually thrilled, to see Africans and other nationatilities on same courses, and graded the same as you Americans and us Europeans. They come from a totally different background and actually have to do real work, to even get materials for high level education. I wholeheartedly support bringing education to everyone, and have yet to see "free certicate" given to someone on a MOOC.