Don't worry, I won't write about every book, and I won't write paragraphs about every book. Although I could.
So, the first two are by Cat Patrick (The Originals and Revived). The Originals is about three clones who have to act as one girl (each taking a part of the day). This was the first Cat Patrick book I read, and it was a really good introduction to her books--science fiction-y and comedic and featuring fantastic female figures (Revived is about a girl who tests a drug that will bring her back to life if she dies).
Hex Hall by Rachel Hawkins is another example of one of my favorite female characters in young adult literature. Sophie is a witch who goes to a school for fairies and witches and shape-shifters, etc., but don't tell me it's "like Harry Potter!" They're both very good, but in very different ways. I think Hex Hall is more like a high school witchcraft and wizardry than a middle school/going into high school Hogwarts.
The Dead Girls Detective Agency by Suzy Cox is about girls who were killed and have to figure out who killed them before they can move on. Need I say more? (Actually, I probably should. This is not The Lovely Bones. It's much lighter, even though, you know, death. Unless you're super sensitive or super sick, don't worry about tissues while reading this.)
The Geek Girl's Guide to Cheerleading by Charity Tahmaseb and Darcy Vance features two girls ("self-proclaimed geeks") who join the cheerleading squad. I loved this book, and if these girls are geeks, so am I, because I recognized myself in Bethany a lot--except for the cheerleading. Not going to happen.
M.A.J.I.C. and the Oracle at Delphi by Katie Mattie--Five girls get superpowers from Greek gods and have to use them to save the world from the Titans. I didn't organize my bookshelf by putting all the best female characters on this shelf, but most of them are here.
The List by Siobhan Vivian is the story of high school students whose lives are affected by the publication of a list of the prettiest and ugliest girls of each grade. I love this book because you get a glimpse into each girl's head, and you realize there are disadvantages to all of their positions, not just the "ugly" girls.
Confessions of the Sullivan Sisters by Natalie Standiford and Brilliant by Rachel Vail are not related, but I'm going to talk about them in the same paragraph. Sullivan Sisters is about three (you guessed it!) sisters whose grandma is planning to cut them out of her will if one of them doesn't confess what she did wrong. All three of them think it's their fault, so you get each girl's story. Brilliant is the third book in the trilogy The Avery Sisters by Rachel Vail, about the three (again) sisters who go through major changes when their mom loses her job (Each girl gets one book). See why I combined these two books into one paragraph?
Thanks for reading through all that rambling, if you're still here. I'm seriously considering reorganizing my shelves with themes like this (girl power?), because I've already got the beginnings of one. Why not?