Annie On My Mind by Nancy Garden is beautiful, touching, full of sugar-sweet moments, but also tackles institutionalised homophobia in schools and even touches on those using religion as their basis for homophobic tirades. It's about two girls, Eliza and Annie, who fall in love only to find that, especially in Eliza's case, that her school isn't ready for her. It contrasts between poor and rich, open minded and closed minded, shame and pride. It's such a stunning book that I found it hard to sleep after reading it.
I read it all in one night, and this was after reading a good chunk of Scott Westerfeld's Goliath, and I don't regret staying up to read it. It was worth every moment.