The above scene serves as the end to the exposition. Before this point, most of the book has been setting up characters like Boo Radley and Dill, however upon the slap of the Radley House, the book has finished setting up it's premise.
"Jem threw open the gate and sped to the side of the house, slapped it with his palm, and ran back past us (...)" (16)
Meanwhile, this scene serves as the true beggining of the rising action, as Scout's life begins to become much larger. Ms. Caroline's rant regarding Scout reading is also the first sign that things are about to begin rapidly changing within the book itself.
"Now you tell your father not to teach you any more. (...)" (19)
The scene with Jem entering the Radley Place to retrieve his pants is an early sign of the direction the novel is about to take. Whilst the next piece of the storyboard covers the beginning of the novel's sudden dive into being more dark in tone, this foreshadows it.
"Then I thought I heard the back fence squeak. It was wishful thinking." (64)
This scene is the start of the novel's deep dive into more mature and dark elements. It's only after this point that such things as Tom Robinson and the more dark elements of Maycomb begin to show up within the novel.
"At the front door, we saw fire spewing from Miss Maudie's dining room windows." (78)
This scene is the very first to introduce a major character during the climax, Tom Robinson. Without this scene, the climax would either make no sense or could never occur.
"You can just take that back, boy!" (85)
Mrs. Dubose's death is the final sign that the book is about to get truly serious. Her death seems to greatly impact Jem's personality, and her death truly sets up the expectation of what is to come.
"That'll do (...) and that's all. Good-day to you." (126)