The character Captain Hook, main protagonist of J.M. Barrie's Peter Pan, definitely attended a British public school:
Hook was not his true name. To reveal who he really was would even at this date set the country in a blaze; but as those who read between the lines must already have guessed, he had been at a famous public school; and its traditions still clung to him like garments, with which indeed they are largely concerned. Thus it was offensive to him even now to board a ship in the same dress in which he grappled her, and he still adhered in his walk to the school’s distinguished slouch. But above all he retained the passion for good form.
-- Chapter 14, "The Pirate Ship"
In later interpretations of the story by authors other than Barrie - for example, Geraldine McCaughrean's excellent 'sequel' Peter Pan in Scarlet - Hook is portrayed as specifically an old Etonian: that is, an alumnus of perhaps the most famous public school of them all. I'm curious whether this specifically is supported by the original text, or if it was first made up by someone other than Barrie.
In Barrie's original Peter Pan, is there evidence that Hook was an Etonian?