When a new, longer set of monkey bars is installed at the park, Caillou is disappointed that he can't climb as far as Leo. He asks his Daddy how he can get bigger and stronger and finds out that eating right, exercising and getting lots of sleep is the best way. Later, when Clementine and Billy join them Caillou finds he can lift up Billy's bike. He couldn't do that last year! Caillou realizes he's getting stronger every day!