Why does Laurie's mother worry about Charles's behavior in kindergarten?

Each day when Laurie comes home from school, he elaborates on Charles's misbehavior and tells his mother about Charles's audacious and violent exploits. Laurie reacts like any concerned mother would and begins to worry that Charles's bad behavior will rub off on her son. After the first week of school, Laurie's mother asks her husband if kindergarten is too unsettling for their son and mentions that she fears Charles is a bad influence on Laurie. Despite her concerns, Laurie's father tells her not to worry—there will always be bad people like Charles in the world, and Laurie might as well meet them now. Ironically, Laurie's parents fail to see that their son is the child causing all of the trouble, and Charles is his pseudonym. Interestingly, they never chastise their son's behavior when he speaks disrespectfully toward them at home or leaves the table without being excused. Laurie's parents also seem to show more interest in Charles than they do their own son; they are constantly questioning Laurie about Charles's most recent exploits. However, they do show concern that Charles may be a bad influence on their son and fear that Laurie will pick up Charles's bad habits.

In the short story Charles, Shirley Jackson creates a story anyone with children can understand. Like mothers everywhere, Laurie's mother worries about Charles's behavior because Charles may be a negative influence on her own son Laurie.  Children tend to learn from each other, and Laurie is very interested in what Charles does each day, taking delight in telling his parents about each exploit.  Mom worries that Laurie may start acting like Charles. The sad part of this story is that Laurie's parents never really question or pay close attention to Laurie and his day at school, but only question what Charles did.  Laurie is their child, and yet in reality he is ignored far more than Charles.  As parents, they leave much to be desired which is why I think Laurie makes Charles the exciting part of his day telling his parents about Charles' antics. At least they will pay attention to the stories if not to him, and making Charles take the blame for the behavior leaves Laurie as the "good child."

Laurie's mother doesn't feel too comfortable about her son's first day at kindergarten, not least because it precipitates a noticeable change in his personality and demeanor.

All of a sudden, a "sweet-voiced nursery-school tot" has been replaced by an ill-mannered, "long-trousered swaggering character," and Laurie's mother is understandably none too happy about it.

When Laurie comes home after his first day at kindergarten, he picks up where he left off earlier that morning. The boy slams the door, throws his cap on the floor, and starts yelling if anyone's there. Whatever Laurie learned at kindergarten, it certainly wasn't good manners.

In fact, Laurie is adamant that he didn't learn anything, hardly an encouraging start to his formal education. His mother is worried. She wonders if kindergarten is too unsettling for her son. As well as being worried about Laurie's toughness and bad grammar, his mother is concerned about a boy at kindergarten called Charles, who apparently is always getting into trouble and might be a bad influence on Laurie.

In "Charles" by Shirley Jackson, what doubts does Laurie's mother have about sending him to kindergarten and what is her husband's opinion?

In the story, Charles, Laurie's mother thinks that kindergarten is a bad influence on Laurie. When Laurie comes home to relate the misadventures of a certain badly behaved classmate named Charles, Laurie's mother is alarmed.

Apparently, Charles has gotten into trouble five days in a row. On the first day of kindergarten, he is spanked by the teacher for being fresh. On the second day, Charles is also spanked, this time for hitting the teacher. On the third day, Charles bounces a see-saw on the head of a little girl. This leaves her bleeding, and Charles has to stay inside during the whole of recess. On the fourth day, Charles has to stand in the corner because he can't seem to sit still during story-time. On the fifth day, Charles is deprived of blackboard privileges because he threw chalk at his classmates.

With the bad behavior of the unfortunate Charles in full display, Laurie's mother feels that kindergarten is too violent and unsettling for her young son. Laurie's usage of bad grammar also convinces her that kindergarten is a bad influence. Meanwhile, her husband attempts to reassure her that everything will turn out for the best. He reasons that Laurie is bound to meet characters like Charles at some point in his life and argues that his young son might as well meet them sooner rather than later.

As time continues and Charles' related antics become more and more fantastic, the whole family begin using Charles' name as an euphemism for any mishaps, misbehavior, or bad attitudes at home. However, when Charles begins to exhibit a string of good behaviors, no one is more surprised than Laurie's mother. Laurie's father, who originally advises Laurie's mother to patiently wait out the full development of affairs at the kindergarten, is just as curious. Eventually, both become intent on meeting this mysterious Charles' mother.

Laurie's father suggests that they should invite Charles' mother home for tea after the PTA meeting so that they can finally meet her and ask her about her son. The story ends on a humorous note when Laurie's mother finds out that there is no such little boy named Charles at the kindergarten.