What does the book burn symbolize?

The Burn Book is a symbol of all the animosity that the junior girls at North Shore High harbor toward one another. It contains a page and photo for each student, becoming almost like an evil counterpart to a normal yearbook. The Burn Book becoming public essentially dramatizes what would happen if everyone simultaneously learned what everyone else was saying behind their back: total chaos. The Burn Book is also a symbol of deceit, given that Regina turns it in despite the fact that it is hers, and causes Ms. Norbury to force the girls to write apologies.