How does the knothole represent/symbolize Jem and Scout's innocence, loss of innocence, and recognition for a need for change in Maycomb in To Kill a Mockingbird?
Scout's innocent discovery of the first sticks of gum in the knothole of the oak brings a warning from Jem that the Double-Mint may be poisoned, just like the pecans on the Radley property are believed to be. It is the first step in the process that begins with curiosity about who leaves the gifts and ends with the realization that they must have come in a friendly display of affection from Boo Radley. It is at first impossible for the children to believe that they could have come from the "malevolent phantom" within the Radley house; they instead assume that the items belong to a school child who has decided to store them temporarily. But when Jem and Scout finally realize that they could only have come from Boo, they take the next step in the friendship process: They try to send him a thank you message. Gone are the terrifying stories about Boo's mutilation of animals and poisoning pecans, and they soon recognize that the gifts could only represent Boo's attempts to be neighborly.
When Jem discovers the knothole sealed and realizes that Nathan Radley has lied to him and his actions are done so simply to prevent Boo from his innocent form of contact with his young neighbors, Jem sees both the dishonesty and cruelty that can be found in well-meaning adults. It is only much later that Jem understands why
"... Boo Radley's stayed shut up in the house all this time... it's because he wants to stay inside." (Chapter 23)