What significance do the following objects have in Part One of the book? What do they tell about the characters or storyline?

On Halloween another kid dressed as the Bleeding Scream gives Auggie a high five when they pass. Perhaps it is ironic that a bleeding scream masked kid gives Auggie a high five. He probably wouldn't have if Auggie wasn't behind a mask. Is a scream the reaction that Auggie perceives kids give when they witness his face?