Frizzle grows Arnold as the Tyrannosaurus attacks the bus, and he scares it away, the class learning that the carnivore only wanted "an easy meal without a fight". In the future, back at the fossil dig site (and before going back to school), they find a fossilized sneaker footprint. It's a fossilized footprint from a sneaker; which was caused by giant Arnold's sneaker (from their time travel to after he fought the Tyrannosaurus; which made Arnold leave the sneaker footprint from his shoe due to his giant size). When Ms. Frizzle says she wonders what giant creature left that footprint, Carlos jokes: "I'd say it was a 'Sneakersaurus'!". Notes Dinosaurs featured: Alamosaurus: Plants Parasaurolophus: Plants Edmontosaurus: Plants Ornithomimus: Meat and plants Triceratops: Plants Troodon: Meat (Meat and plants in real life) Tyrannosaurus rex: Meat First and only time travel field trip. Arnold acts courageously, rather than being unsteady and cowardly as he is normally portrayed. Phoebe does not say "At my old school...". Instead, she somewhat uses Arnold's catchphrase and says, "It's a good thing you didn't stay home today, Arnold". Arnold (about the fossilized egg and when he gets it back to a fossil again) replies, "Well, I should be glad when this egg is a rock again. It's a lot safer". In the Parasaurolophus scene, the "screen" behind the crest of the dinosaur changed color. The Troodon were shown walking flat-footed. The Troodon was shown without a sickle claw. The Ornithomimus and Troodon don't have any feathers, as was commonly thought in research at the time of writing. Dr. Skeledon was played by Rita Moreno, with whom Tomlin shared the role of Violet Newstead from Nine to Five. Tomlin played Newstead in the original movie while Moreno played her in the subsequent TV series. Ornithomimus was more likely to be an omnivore than a true carnivore. So was Troodon. Ornithomimus was also most likely not an egg thief (as depicted in the episode). It was an omnivore and ate both meat and plants. Throughout the episode, the egg is shown being tossed around wildly at different points. Dinosaurs didn't turn their eggs like birds today. Because the embryo inside would have died. Edmontosaurus is seen but not identified. Software adaptation Ms. Frizzle is missing three photographs of prehistoric animals from her photo album of her last trip to the age of dinosaurs. As usual, the user has to