The mood of a piece of literature is its guiding emotion or atmosphere that is created by its setting, plot, characterization, tone, imagery, and dialogue. The mood of Shirley Jackson's story “Charles” is probably best described as perplexed.
Laurie's parents cannot figure out what is happening with their son. First, he has changed from a cute, sweet toddler to a “long-trousered, swaggering character” who doesn't even wave goodbye to his mother on his first day of kindergarten. His behavior is insolent, noisy, and disobedient. He talks back to his father, is rude to his mother, and is generally a very naughty little boy. Yet his parents don't seem to know what to do about it. They correct him verbally, but they don't enforce their words with punishment, and Laurie's behavior worsens. His parents remain completely perplexed at how to handle Laurie.
What's more, Laurie's mother and father are perplexed by their son's constant talk about his classmate Charles. Charles is always doing something horrible at school. He is fresh with the teacher. He even hits the teacher. He refuses to participate in class activities. He throws chalk and makes noise and says bad words. Again, Laurie's parents don't seem to know what to say to their son about Charles. They listen to him, but they never talk to him about why Charles is wrong or how Laurie most certainly should not behave that way. Instead, Charles becomes something of a family joke.
The story (and Laurie's mother) reaches the heights of perplexity at its end. Laurie's mother goes to a conference with her son's teacher, who tells her that Laurie had a tough time adjusting to kindergarten but is doing better (with a few lapses). Laurie's mother wants to blame Charles's influence, but the teacher looks at her strangely and says that they “don't have any Charles in the kindergarten.” Laurie's mother must now come to terms with the greatly perplexing fact that “Charles” is her own son.