That's why it's actually better not to take classes that you have interest in, *if* formal education in that interest is optional.
That is, if you want to learn about chemistry, it's a good class to take. You NEED to learn from someone competent in order to get anywhere.
However, with something more open-ended like creative writing or philosophy (provided it's for interest and not as a path to law school, etc) you're best off just exploring the subject on your own.
Yes, college WILL disrupt your natural rhythm (or lack thereof) when it comes to spending time on the subject. However, it's not the college's fault. It has to have some kind of schedule in order to teach and get things done. The class can't wait around until you're in the "mood" to paint (which might not be until next year, etc.) In a class with many students, it must teach universally according to certain standards and it cannot cater to only you.
So, you're gonna have to be bound to the school's timetable. That's why I took up Accounting. I had no passion for the school to take away.