Andreina Cordova has a 15-minute window to change a life, just a few moments between the dismissal of classes and the beginning of soccer practice.
She wants to speak to anyone who will listen -- about making smart decisions about sex.
She plunges into the throng of students on the sidewalk outside King/Drew Magnet High School of Science and Medicine.
She has memorized pages and pages of information on sex education and sexually transmitted diseases. She's ready to pass out cards from Planned Parenthood, listing services and clinics. She is also armed with condoms.
Andreina is 15. She's been attending Planned Parenthood sex education events since the age of 13. She had just finished eighth grade when she became one of the youngest students ever hired to be a peer advocate in a program whose goal is to reduce teen pregnancy and STD rates.
And that may be why some of the kids at school assume certain things about Andreina.
"People are like, just because she does this peer counseling, she is going to have sex like that," said Bryanna Rivera, who is also 15 and a friend.
But they don't know Andreina.
Popular culture works against anyone trying to push safe sex or abstinence. Sexually charged advertising floods TV; MySpace and Facebook are saturated with come-ons from and for adolescents. Thanks to the tabloids, updates on 17-year-old Jamie Lynn Spears' pregnancy appear almost daily.
More than 360,000 adolescents contract a sexually transmitted disease each year in Los Angeles County. In 2005, the most recent year for which data is available, 5,113 L.A. County girls younger than 18 gave birth -- 3.4% of all births that year.
Andreina does her outreach at the epicenter of the crisis, South L.A., which has the county's highest percentage of teen births and rates of sexually transmitted diseases, according to the county's Department of Public Health.
The statistics aren't just numbers to Andreina; they represent the teenagers sitting next to her in class, on the school bus, at her house.
"These are people that I know," Andreina said.
Asked why a 15-year-old would risk insults, humiliation and rejection to counsel peers on birth control and STDs, Andreina summons the memory of a middle-school classmate who became pregnant and dropped out.
A few weeks after her classmate left school, Andreina attended her first safe-sex awareness event hosted by Planned Parenthood.
She quickly understood her goal: to educate teenagers on how to make wise decisions.
"I mean, I was in middle school. They don't teach you a lot about sex there," Andreina said.
But first she had one large hurdle to clear: her parents.
Cars pack the driveway of Andreina's house in Paramount on a Sunday morning.
Inside, three generations of Cordova women gather along with Andreina's father, Andres, 50. The conversation among the Salvadoran American family alternates between English and Spanish.
Andreina, whom the family calls "Gina," is the youngest of five sisters; four still live with their parents and maternal grandmother, Carmen. All the sisters are in high school or college, and four of them, including Andreina, want to work in healthcare.
Though the sisters regard their parents as traditional, Roman Catholic and strict, both Andres and his wife, Ana Lillian, 49, demur.
The couple dated for a few years and moved in together in 1982, but didn't marry in a civil ceremony until the quinceanera of their first daughter, Jaime, in 1997. It wasn't until their next daughter, Cynthia, had her quinceanera the next year that the two married in the Catholic Church.
"Our parents wanted us to get married," Ana Lillian said. "We didn't see the need for a little piece of paper."
But perspective is everything. Ana Lillian and Andres are now the parents of five daughters who want to stay out late with friends or dates.
"My white friends still laugh when I tell them that I have to let my dad know if I'll be home late," Jaime, 25, said.
"I'm responsible for them as long as they live under this roof," Andres said. "I just want to be in the loop."
The parent-teenager dance is one that Andreina has learned by watching her sisters grow up.
When she asked to attend her first Planned Parenthood event, Andreina said, "my parents at first didn't know what I was doing."
So when Andres said yes, her sisters were shocked.
But Andres explained: "My parents never talked to me about sex. So many of us back in El Salvador just had to figure out things on our own, from our friends usually."
Now Ana Lillian frequently drives her youngest to Planned Parenthood outreach events.
On the day before school closed for a three-week break, Andreina stopped about 12 students on the campus' sidewalks. The girls seemed receptive; the boys, amused.