When the kids from the other camp are getting on the buses, two girls (one wearing a blue-striped halter top and jean shorts, and one wearing a purple T-shirt and plaid shorts) get on the bus in two separate shots.
He goes swimming twice with his camera. Don't think those were waterproof in 1984.
This is supposed to be a summer camp. It's clearly autumn which means that the kids would be in school and not at camp.
Space camp is located in Huntsville, AL, not Houston, TX.
Grace says that other campers tricked her by saying they were going skinny dipping, but since Grace does not swim and fears the water, that would unlikely achieve the effect it did.