I am the Wallpaper -- Mark Peter Hughes

I like the cover art, even though there's no way that the model is thirteen years old and like everyone else on the planet, I'm tired of the Missing Half-a-Head Look*.  But the color scheme is nice.

After thirteen years of living in her sister's shadow, Floey Packer has had enough.  She's tired of blending in with the wallpaper.

This summer, Things Are Going To Change.

The fact that her younger cousins (one sex-obsessed, the other possibly in a position to blackmail Floey) are spending three weeks in her house -- well, it's a curve ball, but there's no way that she's going to let a couple of little kids prevent her from becoming The New and Improved Floey Packer.

Great fun, from the chapter titles:

chapterone:  in which i,
floey packer, bust size 36b,
receive a training bra
or
the cult of lillian

to Floey's journal entries, from her experimentation with haiku:

so long aunt sarah
fly far far away from your
rude ignorant niece

to some truly cringe-worthy moments.  So cringe-worthy that I held the book in one hand and read through the fingers of my other hand while moaning, "Oh, God, Floey... don't... noooooooo".  Literally.

Highly recommended for fans of realistic teen fiction with a screwball twist.  (Think Judy Blume crossed with Louise Rennison.)

*Which is slightly better than the Decapitation Look.  And the book came out in 2005, so I'm not holding the Missing Head against it.