Arthur Season 3 Episode 9 Arthur's Treasure Hunt / The Return of the King >Mr. Ratburn's class is at a medieval fair, competing for a trophy against a very intelligent class led by Mr. Ratburn's former teacher. Mr. Ratburn's class loses constantly until Arthur beats the other class in a "sword in the stone" challenge by figuring out the riddle the challenge's caller recites, and Mr. Ratburn's teacher realizes that Mr. Ratburn taught his class something he himself never did: to think for themselves.