During the final scene, during which Veronica (Kristen Bell) and Weevil (Francis Capra) are talking, you can see a black teen wearing a green shirt walking behind Veronica. Right after he does, it cuts to Weevil and you can see the exact same extra walking behind him.
When Jackie gets ready for the dunk tank, she puts her hair up in a ponytail. While she's on the dunk tank, her hair changes from up to down between shots.
The final scenes with Weevil (Francis Capra) were filmed in front of a green screen with stock footage added later. You will notice a guy walk close to Weevil and not even touch him.
The streakers are wearing flesh colored underwear.