Final answer:
Scout and Jem receive air rifles for Christmas from Uncle Jack Finch in 'To Kill a Mockingbird', which becomes an occasion for Atticus to teach them valuable lessons.
Step-by-step explanation:
In To Kill a Mockingbird, Scout and Jem receive air rifles as Christmas gifts from their Uncle Jack Finch. These gifts are significant in the story as Atticus Finch uses the opportunity to teach his children important life lessons, including the famous adage, 'it's a sin to kill a mockingbird,' which underscores the theme of innocence throughout the novel. Uncle Jack, a doctor who is much beloved by the children, brings joy to Scout and Jem with this thoughtful present.