To add, the Boo Radley game includes Jem being Boo. He acts like a ghost and every once in a while comes up with the scissors and attempts to stab Dill (who is playing Mr. Radley). Scout plays the roll of Mrs. Radley and sweeps the porch. Atticus comes home one day and notices what the kids are doing he tells them to stop, acting as if he doesn't exactly know what they are doing but he does.
Miss Maudie runs a boarding house that hosts both Mr. Avery and Miss Caroline Fisher. She loves to garden. This is important because her home is a large part of her identity.
The Boo Radley game can be found in Chapter 4. It is invented by Dill Harris when he comes to Maycomb for the summer. Basically, what the kids are doing is playacting out scenes from what they imagine is Boo Radley's life. It is a very elaborate game that evolves into a pretty full play as time goes on.
Miss Maudie is a lady who lives across the street from the Finch family. She is a pretty blunt and outspoken woman. She always treats the two Finch kids as if they are her equals rather than little kids and she is always quite supportive of them.