Sociology is essentially the study or how people behave in groups. Why is this useful? Well, this means you'll have a strong understanding of the dynamics that take place within an office, a band, or a group of fans. Understanding how people think, behave, and make decisions when they are in a group of people, can help you understand how to market to teens that often value the opinions of their peers. It can help you understand how to effectively take the lead on a group project, or make sure every Contributor gets a chance to be heard. Of course, I'm not saying any one social class class will give you all the answers, but it will give you clearer understanding of group behaviors and tools for working with groups in the future.
Like sociology, psychology classes can help you understand the way people's minds work. It's a great skill to have in general, but especially when it comes to working with creative people. There are several areas of psychology that deal with everything from personality to addictions. Some psychology classes will even combine marketing and psychology and allow you to learn the psychology aspects of advertising and communication. These courses teach the psychology of marketing and study, for example, why we tune out certain advertisements, how to appeal to certain personality traits, and how men and women view things differently.
In a way, a music performance or recording is just a beautiful demonstration of many aspects of physics. Physics determinates where to place a microphone, how to build an instrument, and how the sound reaches you when you see your favorite performer. Physics is responsible for the sound of your voice and the fact that microphones actually work. So, it can certainly help to understand how all of this works. If your school happens to offer a course in acoustics, that should be especially helpful. On a similar note, if you're really interested in recording, it also may not hurt to take a few electrical engineering classes to learn how wires, circuits, and all of the gear you work with functions.
Sure, there are obvious communications courses to take that deal with broadcasting, press releases, and radio. These of course will be beneficial, but they are not the only ones you can take. Every job requires an ability to communicate on some level and courses in public speaking, writing, broadcasting, and related subjects can help you gain confidence and experience in skills that relate to every job and industry.
Any Business Class
Obviously you know the music industry is a business, so it seems reasonable to that taking at least basic classes in marketing, economics, finance, etc. can help you out. However, these skills are not just important to those who actually want to work on the business side of things. Business skills like marketing, negotiation, sales, and pricing are good for musicians, producers, engineers, and other creators to know. It allows you to maintain some independence and helps you look out for yourself when it comes to signing contracts or making decisions for your career.