I am a prof (definitely not of business) — your profs can help you in some ways (if they are well-connected in their field, or in their community) but only if they know you. It depends on what kind of school you go to how much contact you have with professors vs. grad students or adjuncts (who will teach you just as well if not better. They do not get paid what they deserve so will not have as much time to help you because they likely have other work). The best thing you can learn from a class, any class, of 5 or 500 is how to befriend others, how to contribute to a discussion, pay attention to boring stuff, and how to communicate effectively (in the appropriate medium for your discipline/specific topic). And of course the subject matter.