George is a 4th grade trans girl. Over the course of the book, she comes out: first to her bff Kelly, then to her mother, then to her brother. Kelly, who is a generally delightful and positive character, rolls with it almost immediately. George's mom is freaked out; something that's revealed in later chapters is that the whole family (mother, brother, absent father) have assumed for many years that George is gay, and have all long since accepted her as gay, but trans is sort of a bridge too far.
The self-acceptance / coming-out plot hangs on the structure of a classroom play: Charlotte's Web. George wants to play Charlotte, and actually auditions for the part, although she's slapped down by her (otherwise sympathetic) teacher. Kelly gets the part instead, and George opts for stage crew over the part of Wilbur. But there are two performances, and Kelly and George conspire to pass off Kelly's costume and send George on stage as Charlotte for the evening performance. People are astonished but it all works out.
In the final chapter, Kelly's uncle offers her and a friend a trip to the zoo -- he lives in another town and has not met George, so at Kelly's suggestion, George puts on some loaner clothes from Kelly and spends a day at the zoo as Melissa. The uncle (and everyone else at the zoo) are none the wiser. George's mother also says she's going to take her to a therapist; it's clear she's going to find someone sympathetic, and George notes that she has read on the Internet that the first step in transitioning is usually to go to a therapist so this is definitely progress in the right direction.
For the most part, this book felt a little connect-the-dots-y but it is (I think) the first middle-grade chapter book about a trans kid, or at least it's the first middle-grade chapter book about a trans kid to come from a major publisher.
There are a couple of really nice moments when George comes out to her family. Her brother, over mashed potatoes, assures her that he already knows she's gay and is FINE with it. ("I don't care. My friend Matt is gay. It's no big deal.") She then tells Scott the real secret: "I think I'm a girl." Scott is silent, eats some more mashed potatoes, and then says, "Ohhh. Ohhhhhhhhhhhhhhhhh. That's more than just being gay. No wonder [mom's] freaking out." And then they talk a little more, he says "oh" again, he asks tactlessly "So, like, do you want to" -- he made a gesture with two fingers like a pair of scissors--"go all the way?" and then finishes off with, "Weird. But it kinda makes sense. No offense, but you don't make a very good boy."
I liked this whole scene: Scott has been set up as the super-boyish teenage boy to contrast with the very, very girly George, but he's shown to be very definitely nurturing (in a teen-boy way) -- there's an earlier scene where George is very upset and Scott invites her to come play Mario Kart. He kind of serves as a proxy for some of the readers in this scene (it's a way to discuss gender confirmation surgery the way kids would describe/understand it.) I like that Scott has to take some time just to think this new information through, but that he also affirms George. (Kelly is initially baffled when George comes out to her, but goes home, Googles, and comes in the next day having read ALL THE THINGS.)
The really lovely bit comes at the end of the chapter: "Scott snuck glances her way too, but where Mom's eyes were filled with concern and confusion, Scott looked at George as if his sibling made sense to him for the first time."
The other bit I liked a lot: there's a bit where George winds up in the Principal's office for getting into a fight with a bully. George scans the posters on the walls, and there's one with a rainbow flag and the words, "Support safe spaces for gay, lesbian, bisexual, and transgender youth." George spends the rest of the meeting staring at the sign.
During the play itself, it looks like the teacher is going to intervene during a scene change, but the principal comes up behind her and whispers something into her ear, and she backs off. At the end, the principal approaches George and her mother to praise what a great job she did and to say, "Well, you can't control who your children are, but you can certainly support them, am I right?" She then gives George a hug, tells her again what a good job she did, and whispers, "My door is always open" in George's ear.
Anyway. It's a quick read and it's definitely good to have this book out there.