The scion of a wealthy Boston family, Kennedy spent his mid-teens at Connecticut's elite Choate Rosemary Hall, where he excelled at history and literature - but infuriated the school's headmaster by organizing pranks as a member of an unofficial school club known as "The Muckers."
Those details of the early life of the 35th president, whose term was cut short by an assassin's bullet in Dallas in 1963, emerge in a new exhibit at Boston's John F Kennedy Presidential Library and Museum, timed to commemorate the 100th anniversary of his birth on May 29, 1917.
Pages from a high school scrapbook, diligently filled out by the man who would go on to become the first Roman Catholic president, show he loved ancient history, music and football, as well as "beefing," slang for complaining or arguing. Despite his later fame as an orator, he never got higher than the middling grade of C+ in public speaking, according to the school.
"Got shot at today for calling an old farmer a bad name," reads an entry written by a 17-year-old Kennedy on Oct 19, 1934. "Almost got hit."
The scrapbook pages are among 40 Kennedy relics never before publicly exhibited, with notes extending to his years at Harvard University and the London School of Economics, before his World War Two service aboard torpedo boats and well before his first successful run for Congress in 1947.
Kennedy went on the serve in the Senate before being elected president in 1960, at the start of one of the most tumultuous decades in US history.
"That's why I so love this scrapbook, because it is so revealing about who he was at the time," said Stacey Bredhoff, the museum's curator.
The group took the idea and ran with it, commissioning gold shovel pins and hatching a plot to pile horse manure in the school gymnasium.
"George St John got wind of it and even though the prank never was actualized, it was enough that they would even consider such a thing, so he threatened to expel them all," but eventually relented, said Judy Donald, the school's archivist.
The details of the group's successful pranks may be lost to time. But Donald said an oft-told tale that a young Kennedy blew up a school toilet with a powerful firecracker known as a cherry bomb is not true - while that incident did occur, it was the work of another student a decade later.
"St John was understandably angry," Donald said. "But JFK was not responsible for that one."
(Reporting by Scott Malone; Editing by Jonathan Oatis)
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