This could have been a 5 star book, were it not for the ending, but more on that later... 
 This novel was above all a nostalgia trip. It reminded me of the kind of books that I loved to read in high school. It detracted nothing from the book given that, but it endeared it to me more. 
 The tone was very introspective, being the first person narrative of one of the two main characters, Angel Aristotle Mendoza, a sad, angry Mexican American boy living in El Paso in 1987. He's the loner type and doesn't really have any friends until one summer he meets Dante Quintana and they become best friends. 98% of the book is the wonderful unfolding of that relationship. 
 They are polar opposites. Dante is as open and upbeat, as Ari is closed off and sad, but somehow they bond. 
 We spend the entire novel inside Aristotle's head and the writing does a good job of conveying that. The prose is a lyrical stream of consciousness style that is beautiful and elegant, you can breeze right through it, but it begs the reader to slow down savor it. 
 (view spoiler)[ I've seen many reviews on this book and everyone neglected to mention the homosexual aspect, and I was a little miffed. Not that I have a problem with homosexuality, I 100% don't, but that people didn't mention it as if it didn't matter or they were afraid to talk about it! It's a huge part of this story and the journey of the characters. But I get it, it would have spoiled part of it. Maybe. Whatever. 
 The ending was absolutely SILLY. It was rushed, contrived, abrupt and departed from the logic and tone of the rest of the book. All the musing that the narrator does about his feelings, all the confusion and inexplicable emotions he went through and his parents sit him down and break the news to him that he's gay? Really? With all the ruminating, processing and even the journaling that Ari did, I feel like the character should have came to that conclusion himself. And not only that, we get no hints whatsoever that Ari himself is gay at all throughout the book. So the revelation comes out of left field. 
 It led me to feel that a) originally, Ari was NOT a gay character, and only Dante was and the author went back and tacked on that ending or b) the author intended Ari to be gay and didn't know where to go with it and rushed the ending. I lean towards theory a) because at the end he says something to the effect (AFTER HE ADMITS THAT HE IS GAY AND IS IN LOVE WITH DANTE) "all the anger and confusion, this was the key. I'm free now!" What? It's too much like the author wanted to wrap everything up in a tight little bow. And Voila! Try unbelievable! and not in a good way. (hide spoiler)] 
 So this wasn't a perfect book, but it was a great one. There were so many touching moments and the parents were great characters (which is rare in YA); all about finding out Who You Are and not being afraid to embrace that.