What is the author's style in The Man Without a Face by Isabelle Holland?

Since "The Man Without A Face" is written from the perspective of a fourteen-year-old, the thoughts and feelings expressed in the book are typical of that age group. However, the writing is sophisticated and crisp indicating that Charles, the protagonist, is smarter than he has always been told he was. The reader is privy to Charles' angst over his dealings with his mother and older sister, Gloria. Although ostensibly Charles is planning on passing the entry exam because he wants to attend St. Matthews boarding school, the reader is aware, through Charles' thoughts, that he wants to pass the entries so he can get away from home.