Stephen Jameson's bedroom features a poster of Tower Bridge, London, with the word "London" on it to refer to the show's UK origins. London Bridge is the next one upstream.
While Stephen's student ID is for James Buchanan High School, the fictional Brooklyn high school created for Welcome Back, Kotter (1975), the interiors were actually filmed in a real school, Brooklyn Technical High School. The name of the school's football team, the Brooklyn Tech Engineers, is partially visible on the floor of the gymnasium.