The superintendent was the senior officer and chief administrator of Starfleet Academy on Earth.
During Jean-Luc Picard's time at the Academy between 2323 and 2327, the superintendent was a male Betazoid, and as such, a full telepath; Picard was called to his office at least once.
During William T. Riker's Academy years from 2353 to 2357, the superintendent was a Vulcan who memorized the personnel files of every single cadet. (TNG: "The First Duty")
Admiral Hahn was the superintendent in 2366. (TNG: "Ménage à Troi")
Rear Admiral Brand held the office in 2368. (TNG: "The First Duty")