What impact does Scout's point of view give the story?
Because the events in To Kill a Mockingbird by Harper Lee are from a child's perspective, certain aspects that might be obvious to an adult's mind are not understood by Scout. She struggles with understanding racism and seeing that Boo Radley is not a myth-like monster. She also develops the ability to see a point of view other than her own, something that typically a child can't do. In that regard, it allows the story to be shown in a new light, something unique to the novel that many books do not have the opportunity to explore.
From the beginning, Atticus is trying to instill in his children that you don't know a person until you walk around in their shoes. At first this goes relatively unnoticed by Scout. As the story progresses, she sees the horror of the unjust trial and the mistreatment of Boo, who becomes her savior. Once she sees that he is a protector versus a monster, she is able to grasp the concept of multiple perspectives.
This, along with the innocence of childhood, allows the story to have a more honest portrayal in tone and spirit.