As a student working on a startup I think I can bring some perspective. They are both incredibly good learning opportunities. I'm the business side of things and, for example, there's a big difference between taking an accounting class versus actually having to keep books. My partners have said the same thing in regards to taking their comp sci classes versus actually working on a startup. It's also important to note that education is moving in a way where a lot of our classes can be taken as either night courses or online. We've been able to not have to choose one or the other, but be able to structure our schedules so we have enough time for both. Which in my opinion is the best way of doing things.