This scene is one of Harper Lee’s demonstrations of how the Radley place terrifies the kids in To Kill a Mockingbird. Scout, curled up inside an old car tire, does not initially realize that she has been pushed to the front steps of the Radley’s house. When Jem yells, “Scout, get away from there, come on!” she looks up and sees here she is.
Harper Lee communicates the heightened sense of excitement and childish fear with four exclamatory sentences by Jem within the short space of the passage. His sudden concern for his sister’s welfare is in contrast to his previous actions—he had just intentionally pushed her too hard in the tire and it got away from him.
Scout’s immediate physical reaction also communicates her fear. Instead of immediately running away, Scout says “I froze.”
Jem’s actions also relate fear. At the end of the scene, Jem has to retrieve the tire. It takes him a moment to work up the courage to run inside the gate to get it.