Some users might not want to have to move around as much since many people are interested in more than one school. The goal of internet surfing is to "reduce the number of clicks" to get you to see more, if that makes any sense.
Creating subforums for each individual school will centralize all information pertaining to each school so those interested in one particular school can share information about it easily. This way, IMO, the information is more specific and there will probably be more of it.
It is true that many users are interested in more than one school, so why not divide them into subforums making it easier to compare and contrast? The alternative, I think, is to search keywords finding a thread here and a thread there on school X and one might be inclined to arbitrarily choose one over another in the huge forum instead of having all posts about a particular school in one subforum making it easier to find what he or she wants about that school.
The goal of internet surfing is the reduce the number of clicks? Maybe so, but in the interest of centralizing information thereby making it easier to find what you are looking for I say get over it.
DragonWell mentioned those forums that have more subforums than actual posts, and this is something to look out for. Perhaps, if it looks cleaner, divide the subforums not by individual school but rather individual state, or something along those lines to reduce the lengthy amount of subforms but still make it more specific than the current design.
Also I must say these are merely my opinions, I think the current design is very easy to work with and the mindshare in this forum is impressive overall, good job and thank you! Just consider these suggestions as the thread title suggests.