There are several well-known alumni of The Fessenden School. They include Howard Hughes, the actor Christopher Lloyd, Massachusetts Senators Edward M. Kennedy and John F. Kerry, as well as Porter Goss, former Director of the CIA.
Michael Weatherly James Spader
David E. Kelley
Look at the wikipedia page for the school bud
FDR, Dean Acheson and McGeorge Bundy are probably the most famous.
The Gaithersburg High School is a well known school located in the state of Maryland. While the school is very successful, there has been no well known or famous notable alumni.
Steve Carrell obviously... and then I know one of the Headmasters was an alumnus...
Jeff Probst the host of survivor graduated in 1979 from Newport High School in Bellevue WA!
Ray Flynn, former mayor of Boston and Ambassador to the Catican