Solitaire
Solitaire is, of course, the card game plays all alone. In the book it is also the name of a secret group intent on wreaking havoc throughout the school. Ironically, the Solitaire group is made up of more one than person and winds up hurting others. In this way, solitaire can be seen as a symbol of why people should not isolate themselves, like Tori, the narrator does. It is a damaging way to live.
Wednesday Addams
Tori shows up to a costume party dressed as Wednesday Addams. Wednesday is the notoriously lugubrious daughter of the macabre family from the ghoulish TV show and movies. By dressing as Wednesday, she becomes a symbol of Tori's self-awareness of her own somewhat dark image.
Tori's Blog
Tori mentions her blog several times. She refers to the act of blogging as well. All that is really know about that blog is that she writes stuff she doesn't feel comfortable saying out loud. But her friends don't know about it. And readers aren't exposed to it. Tori's blog comes to symbolize her resistance to opening up to others about her feelings and her distrust of emotions in general.
Lewis Carroll
While walking down the sidewalk, two random girls pass by and one asks the other who Lewis Carroll is. Tori's response to this is to imagine pulling a gun out of her pocket and shooting them before turning the gun on herself. Lewis Carroll—or rather the ignorance of who Lewis Carroll is becomes a symbol of the kind of profound stupidity in human beings that drive more sensitive human begins to murder or suicide as a means of escape.
Gun Lighter
Whether intentionally or not, there is a light shaped like a gun that plays a big role in the novel which becomes a symbol of something far different to American readers than British readers. The would-be anarchists of Solitaire who wants to bring the school down plan to do it by burning, using the gun-shaped lighter. The dissonance between psychotic students attacking a school in England using a lighter than looks like a gun and psychotic students in America attacking a school using an assault weapon endows the lighter in the story with a symbolism impossible to ignore. It is the symbol of the effectiveness of gun control legislation that is enforced with seriousness of purpose.
