Back in the dim days of antiquity of the Eisenhower administration, we had a Halloween Carnival in most of the Houston elementary schools. It was an evening affair with costumes, concessions run by the PTA, cake walks with cakes baked by parents, and other activities. Pretty fun, as a matter of fact. They changed the name to Fall Festival but kept all of the activities the same, to include costumes and a costume contest. (Which yours truly won once, dressed in a set of white long underwear over my clothes, white tube socks pulled up over my shoes, and a pillowcase over my head and arms with a black derby hat on top. Nobody knew what I was supposed to be -- including me -- but they obviously liked it!)
Update to the 1990's: Tex Jr. went to private schools, first Lutheran and then Church of Christ. The Lutherans did up Halloween with costumes (no masks) on the day of, goodies, and visiting each others' classrooms to show off their costumes. The CoC school taught the kids that Halloween was evil, and that they should all be afraid of it.