At this point in the plot of Harper Lee's To Kill a Mockingbird, Scout is now in the first grade. This means that she gets out 30 minutes earlier than Jem and has to walk home alone past the frightening Radley property. One day while walking home, she sees something shiny in the knot-hole of one of the huge oak trees on the Radley property. The shine is coming from the wrapping around two pieces of gum. On the last day of school, inside the know-hole of the tree Jem and Scout find a box covered in gum wrappers and inside the box are two Indian-head pennies.
What those gifts reveal is that somebody is aware of their presence and has been watching them. That somebody is Boo Radley himself. This is an attempt on his part to make contact with the kids and have some sort of communication with them.
The children find several gifts in the tree's knothole that seem to be from someone who watches them pass by each day during the week. They find these in the knothole: chewing gum, gray twine, a medal, a watch, pennies, and boy and girl soap dolls.
When the children pass the Radley house and see the gray twine in the tree, Scout tells Jem not to take anything because it is probably someone else's hiding place.
"Somebody like Walter Cunningham comes down here every recess and hides his things. Listen, let's leave it and wait a couple of days. If it ain't gone then, we'll take it, okay?"
On the third day, they see that the twine is yet there, so Jem puts it in his pocket. One day Scout reaches into the hole and pulls out two small figures carved from soap, one of which is a boy, the other a girl in a dress. "These are good . . . I've never seen any this good!" Jem exclaims.
From the resemblance of these dolls to Jem and Scout, it is obvious that the children have been watched as they pass by the Radley house. Certainly, when Nathan Radley cements this hole, it becomes apparent that it is Boo who has been putting gifts out for the children. In addition, the soap figures indicate that Boo takes an interest in them.
Since Boo put a blanket on Scout's shoulders while she and Jem stood outside in the cold on the night Miss Maudie's house burned, and since has been leaving the children gifts, it seems reasonable that Boo also runs outside on the night in which the children are attacked in order to rescue them from Bob Ewell's vicious assault.
he is watching the kids in the house