Jon,
if you want my honest opinion, I don't think you're going to get jack out of charging people for anything coursework related. Pretty certain you won't have much success in the US, but 3rd world countries, MAYBE.
I am not a pesimist, but don't forget how much free stuff there is out there. For instance, I could go to New Horizons in Cedar Rapids to learn how to operate a database (while at the same time paying them 1000US to do so), OR I could run searches around here to get the answers I need to earn a paycheck. I asked that company once who their customer base was, and the guy said corporate employees who need to keep up to date on software advancements). So there's a great example of someone who is rich enough not to care (the company). Guy also told me that they have very few people come in as indiv's that spend their money on the programs.
Why would someone pay for coursework when there is no benefit to them other than gaining the knowledge, MAYBE? Gonna offer certifications? Honestly, the only people I see doing something like that are either:
A) People who don't understand that they can get it for free elsewhere, or
B) Rich people that browse the web as an online hobby (not too many of these kind out there)
I have no idea what your bandwidth costs are, nor do I know how much per click you get on all of your google ads (I actually block them with software, so I don't even see them!), but it would seem to me that a forum still makes the most money from advertising. Isn't that the consensus among site owners that you know?
By the way, before I started blocking the ads here, I saw some for "ready-made" programmers that you could talk to over in India by the hour, or by the minute, can't remember. Is that really successful? Is that a google ad? If so, then I bet not.
My opinion doesn't count for much around here, but I do know something about getting "something" for nothing. I've done way too much it...