When Caillou and Rosie stay at Grandma and Grandpa’s house, Grandpa uses pop bottles and a rubber ball to create a kid’s bowling alley in the backyard. Grandpa teaches Caillou to bowl, but when he is called inside, it’s Caillou’s turn to teach as he shows Rosie how to play. Rosie and Caillou have a great time playing together and when they come in for a snack they have another surprise: Grandma has made a little bowling trophy for each of them.