For my upcoming English examination, I need to identify some of the stylistic features that Harper Lee uses in her novel To Kill a Mockingbird. If possible, please identify a number of quotations under a number of different ideas and explain how Lee explores them using her stylistic devices (e.g., dialect, symbolism, cyclical structure, setting). Any help is much appreciated.

The narrative of Harper Lee's To Kill a Mockingbird demonstrates clever use of stylistic devices.

Use of an epigraph
The novel opens with a dedication and an epigraph by Charles Lamb: "Lawyers, I suppose, were children once." This quotation ties to Lee herself, who studied law and who narrates in retrospect as a child in her book. It also relates to the words of Atticus when he talks to Jem after the trial. Jem asks him how the jury could find Tom guilty, and Atticus replies, "They've done it before and they did it tonight and they'll do it again and when they do it—it seems that only children weep" (Ch. 22). In other words, the prosecutor and the jury have lost the honesty and innocence of youth, when they may have been able to believe in the ideals of fairness and justice.
First-person narrator writing in retrospect
Lee's use of the adult Scout, who narrates as a little girl of five or six years old, brings to the narrative the ingenuous quality that allows young Scout to use words and ask about words that are offensive coming from adults. Thus, Lee manages to present a realistic look at the Jim Crow South of the 1930s. Also, Scout asks about words' meanings, thus allowing the character of Atticus to express another point of view. In this way, young readers are allowed on their own to deduce from the narrative the injustices that have been done, making for a more powerful narrative.
Social issue novel and bildungsroman
The narration by a more sophisticated adult Scout, but in the voice of an innocent child, allows for a more candid examination of the race issue. The novel also works as a bildungsroman or coming-of-age novel, as Scout moves from childhood innocence to knowledge of racism and social bias and injustice.
Use of symbolism
The use of the mockingbird as a symbol of innocence is effective in connoting the cruelty of the rumors and jokes about Boo Radley and the accusations against Tom Robinson.
Use of imagery
Lee's final chapter (31) is rich with imagery and summarizes much of what has transpired in the narrative in a rather quaint and pictorial style that leaves readers with a lasting impression of the major scenes in the novel. For instance, this passage is rich in visual imagery:

Street lights winked down the street all the way to town. I had never seen our neighborhood from this angle. There were Miss Maudie's, Miss Stephanie's—there was our house, I could see the porch swing. . . .
Daylight . . . in my mind, the night faded. It was daytime and the neighborhood was busy. (31)

As Scout stands on the Radleys' porch, she demonstrates that she has learned the lesson taught her by her father because as she looks around, she has "climbed into the skin" of Boo Radley by envisioning what he may have seen as he watched through his windows.