"So sending him off to middle school like a lamb to the slaughter..." Section I, pg. 10
Early on in the novel, Dad remarks that sending Auggie to a real school would be like sending a lamb off to be slaughtered, which shows just how vulnerable Auggie is assumed to be and how much the Pullmans want to protect him. But going to school eventually shapes Auggie in many positive ways; though he struggles, he eventually comes out on top.
"Your deeds are your monuments." Section I, pg. 65
Mr. Browne's October precept is a metaphor that emphasizes how a person's actions can create a lasting impact. Monuments are created to commemorate people; the precept states that people will be remembered for their deeds, good or bad. This is certainly true of middle school, where kids are known at large for how they treat others.
"But after she died, I held on to that secret and let it cover me like a blanket." Section II, pg. 87
Via will always remember the way Grans took the time to look out for her and cherish her. When Grans told Via that Via was her angel, her favorite, Via let that secret become her security blanket, her reassurance that someone really did care even though her needs were often pushed to the side in her family.
"The universe takes care of all of its birds." Section V, pg. 204
At the end of his section, Justin likens humans to birds, and insists that while the universe may be unkind in some ways, it always compensates in other ways so that everyone is cared for. A bird metaphor naturally implies flight and opportunity -- suggesting that the universe takes care of its "birds" in order to give them the ability to keep flying. For instance, the universe has given Auggie a loving family, the primary thing he needs to take off and soar.
"It had been a long time since I'd been out without my hearing aids, and it felt like I was miles under the earth." Section VIII, pg. 272
This simile illustrates the uncertainty and sadness that Auggie feels after his fight with the older kids at the nature reserve. Without his hearing aids, he feels lost: he can no longer "hear brightly," so that an essential part of him appears to be missing. He feels like he is miles under the earth both because he cannot hear well and because he is so upset about what has happened.
