Final answer:
Atticus wakes the children because Miss Maudie's house is on fire, showing the community's unity and compassion.
Step-by-step explanation:
Atticus wakes the children in the middle of the night because Miss Maudie's house is on fire. This dramatic event is a significant moment in the novel, highlighting themes of community and the challenges the characters face. The fire serves as a catalyst for showcasing the unity and compassion within the community as they come together to battle the blaze and support one another.