From BoingBoing via YT: "He said nine-year-old Beatrice had written to Captain Jack, asking him to lead a mutiny against her teachers.
Depp, 47, has been filming the latest instalment of the franchise in London.
After his arrival, a special school assembly was called and the film star - along with other members of the cast dressed in full costume - walked in.
Depp produced Beatrice's letter and performed for the children for 15 minutes.
But he told the schoolgirl that a mutiny might get them into trouble."