S4·E29 Caillou the Dinosaur Hunter

The whole family goes on a trip to the natural history museum to look at the dinosaurs. Caillou is really enjoying himself looking at the skeletons and learning about the different kinds of dinosaurs. When he momentarily loses the others he knows enough to stay put until Mommy comes back and finds him. And when he realizes he's left Rexy somewhere he learns about the lost and found, and retraces his steps until he finds his dinosaur friend.