I think Boo was laughing. Boo was isolated and didn't really have a childhood so his laughter wasn't really in the interest of the children, but shared in their enthusiasm and ineptness...
The source of the laughter heard from inside the Radley house is likely to be Boo Radley himself. The cause of his laughter could be his reaction to observing the innocence and playfulness of Scout, Jem, and Dill from the confines of his home, or it could stem from his own amusement at the world outside that he is disconnected from.
Scout heard someone laughing inside the Radley house when she rolled into their yard, which made her feel scared and uneasy. This laughter added to the mysterious aura surrounding the Radley family and their reclusive lifestyle.
Scout heard laughter and someone inside the Radley house saying, "Do our neighbors bore you, Dill?" This made her concerned and curious about the mysterious Radley family and their behavior.
Yes, Scout hears what sounds like someone laughing inside the Radley house, but it could have been something else. The source of the laughter is never confirmed.
Boo was laughing because he found the children's' game funny. He was an innocent character and wanted to join in with them but he didn't know how, so he just laughed with them from inside his house.
Scout heard someone laughing inside the Radley house, but she never told anyone about it. This mysterious laughter added to the rumors and stories surrounding the reclusive Radley family.
She heard laughter from the Radley house.
Atticus returned home to Maycomb to defend Tom Robinson, a black man wrongly accused of raping a white woman.
Scout wanted to quit the game because she realized that Boo Radley had been watching them all along, and felt guilty for making fun of him. Rolling the tire towards the Radley house made her see things from Boo's perspective and understand that their games were not harmless but could actually be hurtful.
someone inside the house was laughing (pg.54)
someone laughing!
Yes, laughter is something that can be heard, a concrete noun.
Scout overhears her brother, Jem, telling Dill about a series of small gifts they found in the knothole of a tree on the Radley property, speculating that Boo Radley must have placed them there, suggesting that Boo is alive and potentially watching over them.