In the unclaimed luggage warehouse, Charlie is seen holding a tape player with his left hand. On a following shot, the tape player is gone.
When Charlie dances in the unclaimed luggage warehouse, the floor around him is completely clean with all the luggage to the sides; however, in the shot with all of the kids dancing, things are spread all around the floor.
When Sam (Spencer and Katherine's dad) backs away from his car before it explodes, he is sill fairly close to it. Yet when it actually explodes, he is much farther away.
When Sam's car explodes, the tree is no longer visible through the windshield.
When Spencer hangs up the phone at the airport, the camera goes to his mom. The woman sitting next to Spencer's mom pushes her headband up, but in the next part, it is back down again.
Charlie zips himself up in the red suitcase without putting his hand outside of it. This is impossible since there is no suitcase built to zip up from the inside.
The car that Spencer and Katherine's dad drives leaving Pennsylvania doesn't have a PA plate on the car and PA doesn't have front plates on their cars.