Cages by Peg Kehret

It was so easy. Kit had already been examining the bracelet for several minutes, and everyone else was focused on Marcia - braggy, annoying Marcia, who had gotten the lead in the class play when Kit wanted it, who had a father who was willing to buy her expensive jewelry, who had everything Kit wanted in the world.

Kit slipped the bracelet into her pocket, turned away... and her life changed forever.

She had come to the mall to escape her alcoholic step-father and her too-forgiving mother, to escape her disappointment at not getting a role in the play - but when a heavy hand falls on her shoulder, Kit discovers that she's locked herself into a worse cage.

The police are called, and so is her mother. She has to pay a fine and appear before a court committee. It's the most frightening thing that has ever happened to Kit. Now she's lying to her best friend and to everyone else she knows, scared silly that someone is going to find out what happened, and sure that she's lost every chance at the scholarship she needs to go to college.

But there is a bright side as well - like the hours she spends at the Humane Society petting and playing with the dogs, and the friend she makes there, who teaches her that cages aren't always made of chain links and metal poles... and that sometimes you are the one with the key.