Third grade brings lots of surprises, but one thing hasnt changed a bit--Harry and Sidney are still sworn enemies. And their relationship only gets worse when Sidney accidentally kills Harrys pet spider. But Harry comes up with a horribly funny way to get revenge during a class trip to a scary old prison and a creepy copper mine. nThird grade brings lots of surprises, but one thing hasnt changed a bit--Harry and Sidney are still sworn enemies. And their relationship only gets worse when Sidney accidentally kills Harrys pet spider. But Harry comes up with a horribly funny way to get revenge during a class trip to a creepy copper mine.