OH to be a kid again. Hollywood Lord JOHNNY DEPP was a surprise guest at a London school's assembly this morning. The actor - who is currently filming the fourth Pirates Of The Caribbean movie in Greenwich - took some time out to make an impromptu trip to Meridian primary school dressed as his character Captain Jack Sparrow. His visit came after one of the school's pupils, Beatrice, wrote a letter to him saying: "Captain Jack Sparrow, at Meridian Primary School we are a bunch of budding young pirates and we were having a bit of trouble mutiny against the...