I've had to take an online driving class in the past due to a speeding ticket. (An online class was simply easier to fit into my lifestyle.) Maybe it depends on the company or "school" that you receive the material from, but I don't remember my course taking nearly as long as you've described. It didn't take any longer than the 6 hours that was advertised.
I remember that I had to sit through each module as it was being presented, and I could not skip ahead, even if I had already read through the material quickly and wanted to take the quizzes or practice questions. This was extremely irritating to me, as I am a fast reader and could have covered the material more quickly on my own.