This entire series is a wonderful way to learn history or teach it to adolescents. I find today's generations seem to recall more when they learn through other people (pop songs, celebrity gossip, etc.), so what better way to teach history than through someone else's perspective? Yes, "authentic" diaries would be "better", but would the language really hold the modern student's attention? Did the diary writer know what WOULD be important in the context of history? Probably not.