If he is a US citizen, make sure he gets his visa for Ghana in advance. When I flew from NY-Accra a few years ago the Delta agents were carefully checking that everyone had a Ghana visa. I have an American friend who tried to fly to Accra from London without a visa (telling the BA folks he could get a visa on arrival), but BA would not let him on the plane.
As a student, he will probably need a special student visa,I don't know for sure.