The big difference between coursework code and production code is the size and scope of it. When you finish a course after 4 months you never have to look at that code again. And it's only going to be so big because, over the entire course, you spend at most a few intense weeks on it.<p>I just got a call tonight about some code I wrote that has a sorted history that is well over 10 years old. I work on a code base every day that contains over 6 years of code I've personally written. In education, you rarely experience that sheer amount of code.