Hey Arnold! the Movie (2002)

Arnold is Nickelodeon's football-headed, untucked-shirted, city-living, stickball-playing kid toon star. Arnold lives in his grandparents' boarding house with a group of eccentric grown-ups who don't always get along. Together with his cool-as-ice best pal Gerald, tough-as-nails Helga—the girl who both hates and loves him—and the rest of the gang from the neighborhood, Arnold tackles life in the big city the best way a wise-beyond-his-years fourth-grader knows how. In this film, Arnold goes up against a powerful industrialist who invades the city and buys everything in sight so he can knock it down and erect a huge "mall-plex." Can Arnold and his best friend Gerald find the document that can stop the bulldozers?