The Busy World of Richard Scarry

The Mystery of the Stone Circle (5x34)

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The substitute teacher, Mr. Tough, has a very special field trip for the class: to the ancient Stone Circle. But the field trip is less than perfect when his entire class disappears. The kids have found a way into a series of ancient caves and they realize the Stone Circle used to be someone's home. When Mr. Tough finds them he's delighted. They've solved the mystery of the Stone Circle.