What are the most important classes to take while trying to obtain a mass communication degree?

Well, you won't have much choice in which classes you take--that will pretty much be proscribed for you by your college and department. You'll have some leeway with electives because they are just that--electives. Just know that whatever classes you take will be largely theoretical and/or insufficiently hands-on, so seek opportunities to get as much practical experience as you can get. Internships are the obvious choice, but try to go above and beyond the opportunities usually required and approved by schools, i.e. junior or senior year. It's never too early to do an internship, though be prepared to be told by your school that a) you can't do one as an underclassman, and/or b) you won't get credit for a non-approved internship. Don't let that discourage you--the more practical experience that you have, the more employable you will be. And you know how you hear about how important diversity is? We're not just talking gender and ethnicity, you need to have diverse experience, too. If you're lucky and motivated enough to do multiple practical experiences, try to do different aspects of mass media--tv, radio, newspaper, web/digital, social media, production, business, on-camera, off-camera etc. etc. Don't be afraid to work for free (a.k.a. volunteering). That's what I did when I was starting out and dinosaurs roamed the earth, we've evolved a bit since then and pay interns, but if you're not being paid people LOVE having you around if you're smart and work hard (if you're neither they don't love having you around). And remember those electives--you be you. Follow your passions, even if it may have nothing to do with your intended profession, because you never know when an employer needs someone who speaks Portuguese, knows how to make a roux, or can argue thoughtfully Biggie vs. Tupac. College goes by quickly, it's hard if you do it right, but not as hard as working for a living. This is a chance to think big thoughts--don't let that pass you by.

It depends on what's your focus behind learning mass communication? Do you want to tell a story? Do you want to report a story? Do you want to learn the best method in delivering messages? Do you want to capture a moment? Or, does the technique equipment needed to accomplish those things interest you more than the message?