Audio problem: In the scene when Mud and his "dad" are getting ready for Celeste to come over, Mud bounces a basketball across a hardwood floor but it makes no sound.
Continuity mistake: At the beginning of the movie, Walter had braces, but as the movie goes on, you see him at camp with no braces on.
Character mistake: The Matterass twins are playing a video game, and they argue about whether to destroy Milwaukee or Minneapolis. They decide on Milwaukee but destroy Hibbing Minnesota.
Other mistake: When Steve's playing the national anthem on the roof, it cuts to the kitchen while Gabby's making food. Steve can still be heard playing the anthem but is also present in the kitchen background.