When Grandma Dot comes downstairs and asks Pen and Jason if they were there to help decorate for the party, Pen closes her computer; but when the camera faces Jason, the computer is open.
When Pen and Jason get inside the house after swimming in the lake with their clothes on, their clothes are fully dry and their hair is still in perfect shape like they didn't just get soaked from head to toe. It's clear that they just sprayed a bit of water on the ends of Pen's hair.