I loved the movie and I love this book!!
I'd love to give a 5 to this book, but the idea of pay it forward is not as great as it seems. It could work, sure, but for a limited time: good action, in this world, are limited to people's excitation. That usually doesnt stay for long, a couple of months and just few people would really keep going pay it forward. And the idea would die, soon.
So what would made pay it forward survive?
I think the authoress got it. There was no hope for Trevor's idea to survive without a tragic event, connected to it, that would have made people's heart REALLY change. And so Trevor death came...fast and unexpected as the blade that killed him. That's what I love of this book: the reality never goes completely away, ready to appear and upset the readers. The Happy Ending doesnt exist either, just a mitigated end which is shared between the characters and never accontent just one person. A bitter plea bargain that taste like hope and rebirth... the perfect ending.
That keep us on reality even on a book made by hope and trust on mankind's goodness.