There are no “required” courses for clerking, but it is a good idea to keep your clerkship plans in mind as you put together your second- and third-year curriculum.
Moreover, some judges will like to know that you have taken, or intend to take, certain courses that will come in especially handy given the nature of their docket. Also, always look for opportunities to improve your legal writing. Be careful about when you take S/U courses. If you take several mandatory S/U classes in one semester, a judge may (wrongly) think that you weren’t working to your maximum potential. Finally, be sure to enroll in a few smaller classes which will allow you to get to know your faculty better. The better a professor knows you, the better a recommendation from that professor will be.
For a federal court clerkship, you may want to take Federal Courts which, among other things, will acquaint you with special issues involving the Article III judicial power and the most important federal causes of action. In addition, for your 3L year, you should also consider the Federal Appellate Practice course, co-taught by a federal appellate court judge. If criminal cases or civil rights cases form a significant part of your court’s docket (as they do for the federal courts and many state appellate courts), Criminal Procedure can be very useful. Most judges want their clerks to have taken core courses like Business Organizations and Evidence. Other courses you might find helpful include advanced procedure offerings (e.g., Advanced Civil Procedure; Injunctions) and Administrative Law. If you are interested in a “specialty court” (a court that handles exclusively tax, bankruptcy, domestic relations, etc.) you should obviously plan on taking the available courses relevant to that specialty. If you are interested in NY state courts or federal courts located in NY, a course with some NY state law content would be helpful. Finally, if you are a student, once you have secured a clerkship, you should ask your judge if there are any particular courses he or she would like you to take.