"The Plague" is a mean game that August’s classmates start to play at the beginning of the school year. The rules of the game state that if any kid touches August, they have 30 seconds to wash their hands or they're infected with the Plague. August thinks of it much like the “Cheese Touch” in the book Diary of a Wimpy Kid. Especially in this sense, the Plague comes to represent the truly horrible elements of the Beecher Prep social structure. The structure thrives exactly because individuals can really only become popular by participating in unkind games and other exclusionary practices, reinforcing the novel's assertion that popularity is dependent primarily on putting others down. When the students eventually abandon the Plague, it suggests that the social structure is evolving for the better as students grow up and make conscious choices to behave more kindly.
The Plague Quotes in Wonder
How I found out about this is that Maya Markowitz told me that the reason she won't play Four Square with us at recess is that she doesn't want to catch the Plague. I was like, "What's the Plague?" And she told me. I told Maya I thought it was really dumb and she agreed, but she still wouldn't touch a ball that August just touched, not if she could help it.
And the truth is, though nobody's that obvious about it: nobody wants to hang out with him. Everyone's way too hung up on being in the popular group, and he's just as far from the popular group as you can get. But now I can hang out with anyone I want. If I wanted to be in the popular group, I could totally be in the popular group.
Before she went out, she looked left and right outside the door to make sure no one saw her leaving. I guess even though she was neutral, she didn't want to be seen with me.