Factual error: Claudia and Jamie stay in one of the museum's beds while hiding out in the museum. The card at the foot of the bed claims that the bed itself was the "scene of the alleged murder of Amy Robsart, wife of Robert Dudley, Earl of Leicester". Except that Amy Robsart was killed when she fell down the stairs in her house - nothing at all to do with a bed. The Metropolitan Museum would have done some research into that.
Other mistake: When the kids leave the bus and start walking past the stores, you can see the boom mic in the reflection of the windows.