It is a rainy day and Caillou is disappointed because he will not be able to go play at the park with Grandma. Caillou's mood changes when he discovers an old photo of a younger Grandpa and Grandma dancing.
Leo is spending the night at Caillou's. Mom, Dad and Caillou provide him with all he needs: a sleeping bag to sleep in and a new toothbrush. Caillou would like all these special treats too but he learns that the guest comes first.
Grandma has given Caillou a special spaceship plate. Caillou loves it so much that he carries it everywhere with him and he wants to eat every meal from it.
Caillou just loves his Superbear storybook. Dad reads it to him once but when Caillou wants to hear it again and again, Dad explains that he has other things to do. Caillou decides to make up a story on his own and plays it out with Rosie.
Caillou learns that the best fun is made up and not bought and paid for. When he sees a flyer in the mail about a fun looking water park, he wants to go! But Mom says it's not a good day for it and Caillou is disappointed. That is until they come up with an idea to make their very own water park in the backyard!
When the park is closed for the day, Caillou's friends come over to his house to play. But when no one will share the sandbox toys, or the swing, Caillou wishes everyone would just go home.
When an invitation for Clementine's party accidentally ends up at Sarah's, Caillou learns the differences between the addresses of the two homes. Daddy helps by making up a rhyme.