Answer:
The story begins with Laurie's mother describing her son's first day of kindergarten. This is the day that he swore off his childish corduroy overalls and began wearing grown-up blue jeans with a belt. Kindergarten changes him in other ways, as well; he becomes loud and insolent, slamming doors and talking back to his parents.
Laurie is also full of stories about Charles, the class rebel. In the first few weeks of school, Charles is rude to the teacher, hurts some of the other students, and yells so loudly that it disrupts other classes in the school. He even hits the teacher and kicks a presenter who comes in to show the students how to exercise. During those same weeks, Laurie's behavior also grows worse, mirroring Charles' problems at school. Laurie's mother takes this as a worrisome sign of Charles' influence over her sweet son. Soon Charles' influence begins to take over the whole household; whenever someone misbehaves or something goes wrong, the family refers to it as being a Charles.
Finally, Laurie's mother goes to a PTA meeting, hoping to see an exhausted, apologetic woman that she assumes will be Charles' mother. None of them, she decides, look haggard enough. Eventually, she meets Laurie's teacher and is surprised to hear that her son has had trouble adjusting to kindergarten. However, she brushes the news off as just another sign of Charles' influence. But Laurie's teacher is confused and announces that there is no Charles in kindergarten. It is implied that it was Laurie, not the fictional Charles, who caused all the trouble at school.
