"I named my baby Kyle Patrick," one shouted.
"Mine is Antonio!"
At the urging of an antiabortion activist, they had each pledged to "spiritually adopt" a fetus developing in an unknown woman -- to name it, love it from afar and above all, pray daily that the mother-to-be would not choose abortion.
"Maybe one day you'll get to heaven and these people will come running to you . . . and say, 'We're all the little children you saved,' " activist Cristina Barba said. She smiled at the students in their Catholic school uniforms. "Maybe you really can make a difference."
Thirty-five years after Roe vs. Wade, the U.S. Supreme Court decision legalizing abortion, opponents are pouring resources into building new generations of activists. Young people are responding with passion.
Today's students and young adults have grown up in a time when abortion was widely accessible and acceptable, and a striking number are determined to end that era.
Pew Research Center polls dating back a decade show that 18- to 29-year-olds are consistently more likely than the general adult population to favor strict limits on abortion. A Pew survey over the summer found 22% of young adults support a total ban on abortion, compared with 15% of their parents' generation.
Looking specifically at teens, a Gallup survey in 2003 found that 72% called abortion morally wrong, and 32% believed it should be illegal in all circumstances. Among adults surveyed that year, only 17% backed a total ban.
These statistics should not obscure the fact -- made clear in poll after poll over decades -- that a substantial majority of Americans want abortion to remain legal in at least some circumstances. And millions of young people continue to choose abortion when faced with unplanned pregnancy; every year, 600,000 women under age 25 abort.
But among those fighting to criminalize the procedure, the young -- trained in antiabortion summer camps and political internships -- are increasingly out front.
"You look at pictures of marches [over the years] and the crowds just keep getting younger and younger and younger," said Derrick Jones, an advisor to National Teens for Life.
In Colorado, a teenager last year decided the state constitution should define a fertilized egg as a person. Kristi Burton, now 20, won a court fight about her proposed amendment and leads the campaign to put it on the ballot this fall.
In California, a 17-year-old girl last week filed a lawsuit in federal court for the right to start a "pro-life club" at her San Jose-area high school. A Virginia teen recently took similar legal action, and her school promptly dropped its objection to the club.
Here in greater Philadelphia, the antiabortion group Generation Life enlists teens to hand out literature on beaches and guides them through role-playing to hone their powers of persuasion.
At a recent workshop, Claire Levis, 17, played the part of an abortion-rights supporter. "My friend got raped and you want her to have the baby? How can you ask a 15-year-old to go through a pregnancy? That's nine months of ridicule and pain," she shouted.
Liz Coyle, 16, responded: "It's not the baby's fault. He's never done anything wrong."
Liz then added: "There are plenty of teachers willing to home-school your friend if she doesn't want to go to class when she's pregnant. Or she could go to school, and stand up for herself."
The dozen teens watching burst into applause.