Twelve-and-a-half-year-old Dawn Wiener is a shy, unattractive, unpopular seventh grader living in a middle-class suburban community in New Jersey. Her seventeen-year-old brother Mark is a nerdy high school student who plays clarinet in a garage band and shuns girls in order to prepare for college. Dawn's younger sister, eight-year-old Missy, is a spoiled, manipulative little girl who pesters Dawn and dances around the house in a tutu. Their mother dotes on Missy and sides with her in disputes with Dawn. Their father is a meek, immature, selfish man who sides with Dawn's mother in arguments with Dawn. Dawn's only friend is an effeminate sixth-grade boy named Ralphy, with whom she shares a dilapidated clubhouse in her backyard.