Cesar Chavez speaking in Los Angeles. (Photo Credit: Los Angeles Times ) School holidays are not neutral. They are signals about what we choose to elevate, and what we set aside. When schools drop Presidents' Day but keep Cesar Chavez Day, that is not just a calendar decision; it’s a value judgement.  But more than that, it reflects our changing relationship with history itself. To begin with, neither holiday is required. Although Presidents' Day is a federal holiday, schools