"I'm sure you've never received a letter of this nature before," Alex wrote. "And I'm also quite sure that you'll be surprised, albeit unpleasantly, at the circumstances under which I am writing this letter."
Alex was a student - perhaps the smartest student at Stoney Creek High School, reports CBS News correspondent Steve Hartman. His SAT scores were near-perfect.
"He's a very bright young man," said Colette Judge, his former counselor. "When things were crazy at home, he could focus on school and that made it better for him."
"I suppose this is where I should delve into a brief summary of my life," Alex wrote in his letter. "My parents divorced when I was 2 years old and I have not heard from my father since. My mother was a nurturing and loving person, to which I credit my early start on a path of academics."
In fact, his mom was getting her Ph.D. in computer science when, one day, she got in a car crash and suffered a head injury. Alex said it changed her - not just physically but mentally.
"She would become abusive and neglectful," Alex said.
Through most of grade school and into high school, Alex bounced back and forth between foster care and living with his mother, who every time promised to do better, but never did.
"Which goes into why the last time I was removed from her custody, I pushed for her rights to be terminated - not because I didn't love her - but because, had I not, I would have been placed back with her and the circus would have gone on," Alex said.
That's how Alex ended up at the Children's Home of Detroit, an orphanage. But more importantly, it's in a whole different school district than Stoney Creek. And Alex says he didn't leave his mother just to lose the only real home he ever knew.
"My school means everything to me," Alex wrote. "When chaos reigned at home, I immersed myself in my studies and my friends."
Unfortunately, it's nearly impossible to find any foster home for a 17-year-old boy. Plus, his social worker at the time wasn't even trying anyway.
"Nobody was advocating for him," said Judge. "So he had to advocate for himself."
"I searched," Alex said. "Pulled up court records and I started looking up foster care listings."
He compiled a list of a couple dozen prospective parents and wrote the most important letter of his life.
"Now I ask you to consider fostering me," he wrote. "Thank you, Alex Chivescu."
It was a shot in the dark, but it worked. Last fall, empty nesters Jim and Suzanne Bante took Alex into their home - and hearts.
"We've grown to love him. He's a member of the family. We hope he chooses to stay there," said Jim.
"It was a really nice surprise," Alex said.
He spent his entire senior year with the Bantes. In fact, the only reason he moved out is because, well, Harvard is in Cambridge, Mass. He started this week and already seems well on his way to finding a new school family. Alex is majoring in economics, although he's not exactly sure what he wants to be when he grows up - other than a foster parent, of course.