November 22, 1963 was also the day that Walt Disney selected the site for the future Disneyworld in Orlando, FL while flying over Florida in a plane. That was also the day that The Beatles released "With The Beatles" in England. It would still be a couple months before they started gaining traction in America.
The opening credits for "Gilligan's Island" was filmed shortly after the assassination. If you look carefully, you will see one of the flags in the harbor flying half mast.
You’re right of course...though I can’t recall why we were let out early, maybe a teachers conference, those usually preceeded holidays.