With Scout as the narrator of To Kill a Mockingbird, the reader can expect to more clearly see the failings, hypocrisies, and flaws of the adult world. Much of the book is about the loss of innocence (hence the title, which refers to death of a mockingbird, a.k.a., an innocent creature) and the initiation into the adult world. With this theme in mind, we can see Scout's experiences in the novel, such as her experience of the trial, as steps on her journey away from childhood. Along the way, we see the events from Scout's unique perspective, which, being a child's perspective, often reveals the flaws and illogical nature of the adults in the story. Thus, using the perspective of a child, Harper Lee brilliantly exposes the inherent absurdities of being an adult and dismantles many fundamental parts of the adult world, especially racism. Scout can't understand the attitudes of her racist neighbors and, through her confusion, we're more clearly able to see what's wrong with the racist culture of Maycomb. Thus, though the story is about Scout losing her innocence, her unique narrative point of view serves as an important critique of this process, illustrating the many follies that most adults fail to notice.
The narrator of Harper Lee's To Kill a Mockingbird is Jean Louise Finch, or Scout. She is five years old when her story begins. Given that the story is told from the point of view of a young girl, the narration is very limited (given Scout's age and gender). She fails to understand why some adults act and speak as they do. Scout's main concerns are playing and her family. She refuses to be the proper little girl Alexandra Finch Hancock (her aunt) wishes her to be. The story gives readers an honest look at both her childhood and the things which happen around her.
Scout's failure to filter her thoughts, prior to her speaking them, illustrates precisely how some children act. Lee's child narrator illustrates for readers the reality of questioning life, the reality of growing up, and the reality of "bad people" simply existing in the world. Therefore, readers can expect to learn about how the world looks from the point of view of a young girl who is struggling with being a girl, being young, and the concept of prejudice.