While reading Harbor Me, I felt like I would want to tell everyone I know to read it; afterward, though, I feel a little bit of unease about the impulse. Books for kids sometimes get a little manipulative seeming: like the author wants you to feel a certain kind of feeling, a certain kind of way, and so pulls the strings to make that happen. All writing does this, but middle grade writing can get a little blatant about it, and doesn't always deliver anything else of value.
This book is emotionally intense; it's basically nothing but kids feeling emotions about hard real life stuff. The format, which involves a certain amount of monologuing and kids recording themselves on a tape recorder and listening to it later, could be distancing. But for me, reading this was immediate and visceral, to the point of being difficult to get through. I cried, I'll be honest. I have a lot of feelings about aunts and uncles who parents kids, and this book brought them ALLL up.
Did I learn anything new? Not necessarily. Maybe I didn't need to. Sometimes it's good to have a book that makes you ugly cry but then you forget about it in a week. I'm not the target audience, and maybe if I wasn't an extremely online adult I WOULD have learned something new that I would have taken and kept in my heart forever. I don't know.
Would I recommend it for RH? Yes. There's a lot of grief in this book but not self-harming or suicide, and all the violence happens off screen. Plus, the conceit of kids getting together just to talk their shit out is kind of inspiring.