answer:For universities, it’s a weekend where they try to get a lot of alumni to come back to visit the school. It’s always done on a weekend with a home football game, the homecoming game. It’s not as big of a deal for the current students. High schools simply have a home football game and a dance. As far as I know, there is no big push for alumni there; it’s mostly for the current high school students. I don’t have time to read all of it, but after skimming the top, it looks like this wiki article will be helpful.