Arthur's experience babysitting for the terrible Tibble Twins is as challenging as he expected, but he finally gets control by telling them a spooky story.
Unable to think of an idea for a science fair project, Arthur borrows a model his father made in third grade but feels bad about it even before he gets into trouble.
Francine is embarrassed by her old bicycle, which was once her father's, but when she makes up a story about the bike being stolen, she finds that it only causes more trouble for her.
Arthur and his friends try to find a substitute to attend the Father's Day picnic with Buster, whose father is not around much since his parents' divorce.
D.W., Arthur's little sister, tells all about what it is like to be in preschool, including essential information about such topics as bathroom breaks, storing things in a cubbie, and sharing at play time.
When Buster rescues a cat stuck in a tree he is treated like a hero, but when he begins to enjoy his celebrity a little too much, his friends devise a plan to bring him back to his old self.
When his father takes him to visit Vermont, Buster sends postcards to his friends back home telling them what he is learning about maple syrup and the "mud season."