Breaking night : a memoir of forgiveness, survival, and my journey from homeless to Harvard / Liz Murray.

Enhanced descriptions from Syndetics:

In the vein of The Glass Castle , Breaking Night is the stunning memoir of a young woman who at age fifteen was living on the streets, and who eventually made it into Harvard.
Liz Murray was born to loving but drug-addicted parents in the Bronx. In school she was taunted for her dirty clothing and lice-infested hair, eventually skipping so many classes that she was put into a girls' home. At age fifteen, Liz found herself on the streets. She learned to scrape by, foraging for food and riding subways all night to have a warm place to sleep.
When Liz's mother died of AIDS, she decided to take control of her own destiny and go back to high school, often completing her assignments in the hallways and subway stations where she slept. Liz squeezed four years of high school into two, while homeless; won a New York Times scholarship; and made it into the Ivy League. Breaking Night is an unforgettable and beautifully written story of one young woman's indomitable spirit to survive and prevail, against all odds.