Who is Mr. Guareschi from The Wednesday Wars and what is their importance?

Mr. Guareschi is the school principal at the beginning of the novel. Mr. Guareschi is perceived as not a nice person and is described by Danny Hupfer as an up and coming dictator of a small country. However, it is Mr. Guareschi who determines that Holling does not need to repeat math, and therefore it is because of Mr. Guareschi that Holling is able to learn Shakespeare. Mr. Guareschi spends much of the novel chasing the escaped rats in the school and planning for the yearly achievement tests. He shows his care when he and Mrs. Baker take Holling to the emergency room following his saving of his sister, but he is still given "administrative reassignment" following the school board's experience with the escaped rats. Although Mr. Guareschi is not a main character in the novel, he does represent one of the forces Holling faces throughout the novel.