This is something that I have been thinking about the last few days, and thought a little discussion would help me come to a conclusion.
With sites such as Khan Academy and Coursera popping up in the last few years, teaching yourself a concept or topic is becoming easier and easier. These sites, in addition to the communities that spring up around and for them, seem to make attending an actual class obsolete. The way I think of it is the video or lesson is analogous to a teacher, while forum posts or discussions about said topics are like the classmates. This seems to be an effective system, and it makes one wonder if there are any advantages that actual classes (i.e. in a classroom setting) have over these new online lessons.
One obvious advantage brick and mortar schools have is their access to resources. In many classes, especially science classes, lab activities are vital to understanding a concept. I can't see any way that online lessons can offer these opportunities short of each person buying the equipment themselves. Clearly this is unrealistic. Another advantage that I thought of was ready access to a teacher or expert on the subject. While internet forums often provide a means of communication with experts in a field, this is not always the case. In an actual school, the teacher or professor is usually available for students to ask questions.
The question I am left with is this; Can one teach themselves online to the same level of proficiency that they would have if they were to have taken a course at a university?