Will-Yum, Elwood, Skinny and Sniffy form a secret club. Mary and Madeline plan a trick on the boys to get them to reveal the "secret" of the club.; Skinny coaxes Will-Yum to run away from home with him, but Will-Yum's mother convinces the two to go camping instead.; Under Genius's direction, Will-Yum and Sniffy build a fast soap box derby car--that doesn't have any brakes!; Will-Yum plays doctor with Sniffy as a patient.; Madeline and Mary try to get Will-Yum to play house with them.; Will-Yum gets a job at the drugstore selling ice cream cones, but his generosity puts the store out of business.; Will-Yum and Whizzer have to see for themselves if a "wet paint" sign is correct.