Cori Stern's spirit called her to the poorest corners of Africa -- most recently to do humanitarian work at a refugee camp in Ghana. It's home to more than 40,000 displaced Liberians.
"I am passionate about Africa," she said. "I'm passionate about the people here. But there's so much richness of spirit, and of family, and of community. And I feel like you should go where you're called to go, and this is where my spirit calls me."
It started three years ago when Stern, a 37-year-old screenwriter from Los Angeles, had an epiphany.
She was reading about a Kenyan orphan who couldn't afford her school fees.
"I realized that maybe I could find a way to pay her fees," Stern said. "It was just like $200, and so I paid for it, and within a couple of weeks she had graduated from high school. And I thought, 'Oh, my gosh. Can it really be this easy?' And the answer was 'Yes, it really can be just that simple.'"
That revelation spurred Stern to go to Africa. Everywhere she went, she saw need. The camp in Ghana was no exception. It lacked basic necessities like food, water, medicine.
Combatting HIV in Newborns
In a place where 15 percent of the new HIV cases are caused by transmission from mother to newborn, there was no prevention program. So Stern started a workshop to teach women how to administer a drug that helps prevent such transmission.
Now many more babies in the camp are born HIV negative.
Stern soon recognized another daunting problem: There was no school for the camp's most vulnerable children -- those orphaned or abandoned by war. So she and 15 friends pledged to raise money and build a school for them.
"The kids who are going to be going to this school, they've been separated from their parents during the fighting," Stern said. "They've been dealing with just a lack of someone to really focus on them and care about them and give them a solid education."
Through Internet fundraising, bake sales -- whatever it took -- they raised $50,000. The school opened today with more than 500 students.
"Sometimes I do get overwhelmed," she said. "But then I think about that quote, 'To the world you may be one person, but to one person you may be the world,' and I think that if one person can go out and make a difference in one other person's life, and if we all did that, it would be a great place."
ABC News' Elizabeth Vargas filed this report for "World News Tonight."