I'm not a game design expert. I'm not in the gaming industry at all, except as a consumer. My son, on the other hand, has expressed a desire to "play test games" as a career. I thought, okay, let's check it out.
Game Design for Teens is an introduction to the game design world (a complex, very technical realm), with the purpose of creating a game design document.
Good: This book is written to the level of its intended audience.
Good: It includes many good/relevant graphics.
Good: Not designed to be a science book.
Good: Keeps to the purpose/focus of the book with many good/relevant anecdotes.
Other: It is a bit verbose/complex at times.
Impressions: Good for young people interested in game design/development.