Yes, this is about a girl, and she thinks girl thoughts at first, worrying about a boy a little, and even once mentions the thing that happens to girls once a month. No boy wants to hear that. Miranda's world is changing. She lives with her mother and brother, with another brother of to college. Her father has remarried and is having another child with his new wife. Sounds thrilling for boys, hmm? But get this: the payoff in the second half of the book is worth it.
See, the rest of the world is changing, too: an asteroid hits the moon. At first no one is too concerned. There are at first some minor effects here on Earth. But as the days and weeks go by, people notice things. Tides are stronger. Volcanoes are more active. Weather is.. weird. Cold. Relentless. It's the end of the world as we know it. Yes, this story is really more about the intense and terrifying struggle to survive in the wasteland that is rural Pennsylvania in the aftermath of this natural disaster. Little food, no people, no communications, nothing but themselves.
The scariest and most powerful part of the story is the fact that this is a natural disaster. There is nothing we can do about it should it really happen. (It can't, at least not the way it is described, but that is neither here nor there.)
There are two sequels so far. Maybe I'll tell you more about them later. One of them, The Dead and the Gone, likely would more obviously appeal to boys.
Sell this book using the disaster part. Tell the boys that the first hundred pages are just a setup if they hesitate. This is, like Across the Universe, a science fiction novel, even though in this case it isn't about spaceships or aliens but nature. Still counts.