It was like having a chestful of bats, beating their wings, fighting to get out.
-- Evan (Chapter 1 paragraph Page 4)

Importance: Evan is explaining how he feels when his sister comes down into the basement and won't leave. He's upset about the letter and is feeling very resentful. The fact that he's in the basement, the lowest part of the house, also parallels his mood, and ties into the analogy of bats struggling to get out.

Evan knew he was being mean, and he hated being mean, especially to her.
-- Narrator (Chapter 1 paragraph Page 7)

Importance: This quote is important because it establishes how Evan felt toward his sister. The quote shows that he would much rather be her friend and brother rather than someone who is at odds with her, or a classmate, even. He is so humiliated that he can't think straight and even while he's being mean to Jessie, some part of him is appalled.

This is a puzzle...
-- Jessie/Narrator (Chapter 2 paragraph Page 11)