To Kill a Mockingbird 4-6

Things start to get really interesting in these chapters. For example, the incident with Scout finding the gum in the tree. When I read this part I started thinking that maybe it could possibly have something to do with Boo Radley. Maybe Boo just put it there to attract attention or make people think its a sign. Another thing i found interesting was near the ending of chapter 4 where it states,"Someone inside the house was laughing". At first I found it to be quite creepy because of the reputation that the Radley house already has. Then I started thinking that maybe it wasnt the Radleys. Or it could be but, nobody knows what really goes on in that household.