Basically every character who wasn't awful was a delight. Betty is the Grandmother I'd always wanted. Supportive teachers also amaze me. I loved that Izzy was given the $50 with no expectation to succeed or pay it back, just because it would be a great experience for her to try, even if she didn't win. And her romance was adorable in how well it fitted her. It's not cute in the general sense, but they do get on well. It was shallow, but then again, it's not the main focus of the book. If it was necessary to have a romance is another topic, but here I think it works. He also does show that not every male in this book is awful, so I would say that the romance was a necessary inclusion. There are also characters with shades of grey, such as Zack. It must be awful having most conversations you have bring up your father in some way, and I would have actually liked to see more of him as a reasonable human being. Ajita is basically the best best friend you could want in Izzy's circumstances, too.
Spoiler: I didn't want to spend any review time talking about Daniel, but I guess I would have to bring him up somewhere. Boy, does he remind me of some guys I've dealt with. What. An. Arsehole. [/spoiler]
What Izzy goes through is not dissimilar to similar events that have happened to real people. I'm thinking predominantly of leaking of celebrity nudes and revenge porn, but some people may know other examples. I was going to say "her life shouldn't be ruined because of a mistake" but it wasn't even a mistake, because it literally shouldn't have happened to her in the first place. Even her sending nudes was well within the bounds of acceptability. Izzy's eighteen*, making this an adult deciding to do something just for the hell of it. If you think it was wrong, I suggest rereading this book, and ask yourself why.
Izzy does make a serious mistake at one point, when she tells that Ajita is gay. This wasn't Izzy's thing to tell people - Ajita gets to decide who knows and when and how to tell them. However, much of the audience of this book will likely be teenagers. Some of them may not be aware of the consequences of giving away someone's sexuality and why you shouldn't do it. I'm not saying that makes Izzy's actions in the book okay, but it does mean people may learn something. Izzy is only a teenager, herself, and therefore will make mistakes. It's only natural. And no, being a full adult in the eyes of the law and still being a teenager prone to errors in judgement can coexist. Even at eighteen, you won't know everything, and you can still develop as a person as an adult.
I will say that some of the syntax reads more British than American. It can be jarring for those who are not used to it. Expect it before going in, remember that it is written by a British writer, and bear in mind that there are a lot of books set in Britain where Americanisms have crept in, too. Those sort of books can throw me right out of the story when I read them. If I'm honest, it still threw me off in this one, too, but I'll give it a pass.
Edit: Since I didn't state this anywhere, the reason British terms sound weird in this book is because it is set in America, but written by a UK author.
* If you are under eighteen, however, please don't send nudes, ever, because distribution and possession of them comes under child pornography laws. Make sure whatever you do is safe and legal. I am disappointed that this point was never brought up, because this book could have been a good way to educate the target audience on best practice for sending nudes. In addition to "don't do it if you're underage" there's also "don't show any identifying features" and "only share them with people you trust." As well as if they ever do get leaked, it is absolutely, 100% not your fault.
I would recommend this book to anyone growing up and trying to make sense of how women are treated in society.
