On the surface, Beka Lamb is just an unruly teenager. She fails her classes, and her parents think she is just being ungrateful about their sacrifices. She gets in serious conflicts with her parents, but they categorize all her behavior as simply "rebellious."
But actually, it's fairly obvious that there is a layer of analysis missing from the book. That's exactly the point, because Beka is disenfranchised, and the reader feels disenfranchised too, because the book conveniently ignores the most compelling arguments against her parents. We just see Beka kicking and screaming, trying desperately to tell her parents that she's struggling in her mental health. They don't see her as a real person, yet, and their view of mental health is not sufficient.
Beka is mourning a death, the death of a best friend who shared secrets with her. They were two peas in a pod—both were poor girls who went to rich people school, because their parents thought it would ensure their success, but Toycie dies. Private school didn't stop life from being difficult before that either—Toycie's similar family dynamic led her to seek intimacy in her love life, and she became pregnant.
What Beka really needs is to be able to talk through her problems with someone. That's what she had in Toycie, so that's the part of loss that will sting the most. She doesn't communicate well with her parents because they misunderstand her and patronize her, but they don't understand that they're condemning her to serious mental health issues by ignoring her point of view. When she finds someone to talk too, she will feel a lot healthier and happier, and perhaps her grades will go up, but if not—at least she'd be healthy.
