RELATED: Photos from the Teen Effort Party

“I drove around today picking up checks. We have 350 people coming so far,” Harry Sitomer said just as guests were starting to arrive at the second annual Teen Effort Party Friday at the Mandarin Oriental to benefit the Mount Sinai Adolescent Health Center.

Dressed in a suit, cell phone in hand, the Riverdale Country School senior, bound for the University of Pennsylvania, looked every inch a professional fund-raising machine. And so did most of the other private-schooled teenagers, like Samantha Perelman and Justin Effron, at the $150-a-ticket party, which featured a buffet dinner and performance by R&B singer Kat DeLuna.

Affluent adolescents have lots of obligations, and yet on Friday they fulfilled one that is typically left to their parents: the dressy charity event.

Mr. Sitomer and his co-chairwomen, Rachele Trentalancia, a senior at Horace Mann, and Elizabeth Sacks, a senior at Dalton, led the effort at weekly committee meetings on Sundays, starting in late November, once the pressure from college applications had eased up.

Ellie Monahan wrangled a raffle item from her mother, Katie Couric: a private tour of CBS, where her mother anchors the Evening News.

“My mom told me to make the event sound appealing, be friendly, and do your homework,” Ali Lebow, daughter of deputy mayor Patricia Harris, a close adviser to Mayor Bloomberg on his philanthropy, said.

The Mount Sinai Adolescent Health Center has for more than 40 years provided free health care to 10,000 adolescents between the ages of 10 and 24 annually, primarily in the five boroughs. Its leader, Dr. Angela Diaz, was once a patient herself. The center offers mental health counseling, reproductive health services, and substance abuse prevention programs.

“It’s an amazing place,” Mr. Sitomer said, admitting that most of his friends probably don’t worry about health care.

“When I visited, I was completely inspired,” Miss Sacks said. But she was not allowed to volunteer. “They were afraid I’d run into kids from my high school,” she said.

A girl approached in a tan and black dress falling at the knee, one of the more modest hem lengths of the night.

Miss Sacks kvelled: “Zoë, you look gorgeous,” before turning to me to explain, “That’s Zoë Norman-Hunt, the daughter of the former president of MTV Networks, Christina Norman. She’s a committee member.”

But social cachet mattered little in comparison to the committee’s results.

“When we raised $127,000 last year, I was shocked. My goal was $50,000,” Miss Sacks, who plans to major in classical studies at Colgate, said.

Asked what makes a good committee member, Miss Sacks replied, “Someone devoted, someone not afraid to walk into their hair salon and ask for a contribution, someone not afraid to make phone calls. To succeed, you need to be able to ask for help.”

One thing she has learned in her two years of working on this event: “It’s a lot more effective when a teenager asks for money than when an adult does.”

“These kids have worked it like you wouldn’t believe,” Miss Sacks’s mother, Patty Sacks, who is the president of the advisory council of the center, said.

Mrs. Sacks is grateful for the additional funds. The center is in the early stages of a $22 million project to increase its space by two floors, expand the number of patients it sees by 50%, and expand its research activities.

Miss Sacks wants to be a part of that future. “I’m working for the center for the rest of my life,” Miss Sacks said.

“We need you,” Mr. Sitomer called out to her.

A few photographers were trying to organize a formal portrait of the committee, but the 25 or so teenagers present couldn’t seem to stand still.

Miss Sacks appraised the situation. “I’m the one who yells. I keep everything in line,” she said before walking in the center of the crowd.

“Everybody, listen up,” she said loudly, clapping her hands together. In a few minutes, the portrait was done.

agordon@nysun.com

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