I finished out my Bachelor's (from having an Associate's) completely online at an established, bricks-and-mortar state school (Troy). Now MIT it ain't. But it's regionally-accredited, and the price was right. Overall, it was a good experience, and, for the classes that weren't already old hat for me, I did learn a lot. Some professors were good, others not so much. Some were fantastic.
Yes, I had to take some classes I could probably have taught. But as others have said, that's pretty much how it is everywhere. Remember: Getting your degree is only partially about learning new things. It's also--perhaps mostly--about getting proof that you've learned things. Many classes are more about demonstrating knowledge (by passing) than about gaining knowledge. It's a big, fat certification.
And yes, I had some classmates whose class postings would make me wonder not only how they managed to get admitted to college, but how they even graduated high school in the first place. Some would even copy-and-paste their posts directly from Wikipedia--underlined links and all. Ugh.
But there are goobers in B&M classes too. You just don't normally get to read or hear what they have to say. They have the option of participating very little in class and just turning in their papers directly to the prof. In an online class, there's usually a specific participation requirement in terms of number of posts, etc. You see a lot more of everyone's written work.
When it comes down to it, all education is self-education. No one can educate you--they can only facilitate you doing it to yourself. If you want to stay where you are, then go for it. Trudge along, get the grades, learn what you can from the textbooks and elsewhere, and get your "certification."