She and her family are about to lose their house.
"When you got the foreclosure notice, what went through your mind?" CBS News correspondent Seth Doane asked Shelby's mother, Melody.
"It was just devastating," she said.
Melody has taken pay cuts to keep her job at an electronics distributor. And the bills have piled up - as her ex-husband owes them $88,000 in unpaid child support.
"It just washes over you, just thinking, how did we get here. And you're going over everything in your mind and just, you know, it's like it's surreal. It's not really happening," she said.
Like an estimated 2 million other kids across the United States, Shelby is directly impacted by the foreclosure crisis.
"Was there a time when your mom sat you down and said 'Look, we're having a tough time?'" Doane asked Shelby.
"She never really had to do that. I could tell on my own. She was getting bills she couldn't pay; she was crying when she would get the bills. And so she never really had to. I just kind of got it."
Shelby "got it" - and then she got a job.
As a server at a retirement community, she earns about $7 an hour - or $100 a week.
"Where does that money you make go?" Doane asked. "Where do you spend it?"
"I give half to my mom, pay for my phone and school clothes and toiletries and things like that," she said.
It goes fast.
"Yes," she said.
Her friends, using their parents' money, are the first to buy. Shelby takes her time and hunts for bargains.
"Ok, so, grand total is going to be $56.71," a clerk says.
Does Shelby feel like she can make a difference?
"I know it's making a difference," she said. "Because it has to be. I mean, I'm spending all my paychecks, but sometimes it feels like it's not making any difference."
But, it is making a difference at home - even if it won't stop the foreclosure.
"How is it, realizing that you need your 16-year-old daughter to help pay the bills?" Doane asked Melody.
"It's hurtful, it's devastating, it's humbling," she said.
But it's also a life lesson for Shelby - learning the value of a dollar and the value of helping out, any way you can.