I got a lot of surf in college. A few semesters suffered but over all I did well and learned a lot. It helps that you can schedule your own classes. By my sophomore year I was taking most of my course load on T/Th with M/W completely off to work or play. Work in some some paying, flexible odd NYC jobs and you can even pocket good money for little effort. It helped that decent surf was a 50-70 minute subway ride away. You could even study on your commute.