The computer starts to go wacky - it's doing their chores over and over again! so Ms. Frizzle turns the kids into a floppy disc and sends them inside the computer.
Ms. Frizzle's class is holding a recycling drive. But when Phoebe loses her necklace, the kids hop on the bus to track it down. You'll never guess what happens when the class gets to the recycling center.
The class finds Ms. Frizzle inside her closet - playing pinball! But this is no ordinary pinball machine - it's played with light pulses, not steel balls. The Friz has to light up the six colors of the rainbow to win the game and the kids want to help her.
When Ms. Frizzle and her student Arnold follow an underground passage beneath Craig's Castle Shop and find themselves in the middle of a siege of a 12th century English castle, they learn a great deal about both castles and the Middle Ages.
