The book Nineteen Minutes by Jodi Picoult, which is about the shootings in Columbine High School, contains many ideas for a thesis. Which ideas you choose to emphasize would make up your body paragraphs and thus your thesis. Ideas in the book which still are taking place are the bullying which causes so much pain, the gender confusion and identification which creates another painful topic, the issue of the guns which again is in the headlines, the school itself which is also in the headlines currently with Sandy Hook Elementary, and the tragedy which you know is coming at the end of the novel. A thesis I might consider would be that the novel shows the pain of youth and its results if no one intervenes with the deaths and violence the guns create when used by the students. Pain is shown through the pain of the main characters with bullying, the power or popularity structure of the high school, and the tragedy of the isolation of those who don't fit the accepted forms of gender orientation. Gun control is another thesis you could make fit here, but I don't really see the book's thesis fitting into that issue completely.