The film begins as Lizzie McGuire prepares for her Middle school#United States graduation with one of her two closest friends, David "Gordo" Gordon. Her other best friend, Miranda, has chosen to skip the graduation ceremony in favor of a trip to Mexico City to visit relatives. During the ceremony, Lizzie trips onstage and accidentally brings the curtain down on her fellow graduates; this causes her to be teased by her ex-best friend Kate Sanders and her younger brother Matt. After graduation, Lizzie and some of her class embark on a trip to Rome, Italy, chaperoned by their future high school principal, the rude and stern Angela Ungermeyer. To their dismay, Lizzie and Kate are assigned to the same hotel room.