They'd seen white people before on that West Philadelphia block - there were those two on the corner with dreadlocks who moved to San Francisco. But the tall dude who introduced himself as Mr. Leonard was potentially freakier - he kept offering to take the neighborhood kids to baseball games.

"We watched, and we watched," said Barbara Grant, who lived two doors down, and had an 8-year-old daughter who complained of having nothing to do.

For a month, Bonarek heard "Thanks . . . we'll call you" after he offered to help. It sounded too good to be true. No one called.

Then came his first taker - a girl named Ahnesha, whose mother agreed to let him walk the girl to the recreation center where league play was starting.

If it took one month to get one kid, it took three days to get the next 10. Now there are 50 - neighborhood children, ages 8 to 14, whom Mr. Leonard knows by first name - kids who drop by after school five days a week, and sometimes more.

His is the place with all the bikes on the porch and the three friendly mutts, and the door that's almost always open.

Think of Bonarek as an inner-city surrogate soccer mom, shuttling kids to healthy activities, keeping everyone on course, teaching them a thing or two along the way.

Tuesday he could be found corralling kids to ride to St. Mary's Episcopal Church on the Penn campus, where an organization called Neighborhood Bike Works teaches children to repair bicycles.

One of his charges, 12-year-old Dejan Taylor, had spent 25 hours refurbishing a three-speed cruiser. Bonarek wanted her friends to watch her graduate from the program, so around 3 p.m. he was playing the Pied Piper.

"You going?" Mr. Leonard called out to Emrold Smith, 12, as she walked home from school.

"We having a party?"

"Always do on graduation. Pizza."

"I'm going."

Soon they were off - Bonarek leading four girls riding bikes down Locust Street, all wearing helmets.

Andy Dyson, Bike Works' director, calls Bonarek a godsend. "When he's there, we know the kids are getting a safe ride home, so I don't have a freaking heart attack."

A couple of weeks ago I asked Bonarek what motivates him.

"Being a child of an addict and a person with cancer, that's what you do - take care of people."

He's 33 and solidly built, with a brown buzz cut, chin beard, and rectangular specs. He was sitting in his kitchen, MacBook open, trying to keep the pit bulls from licking his visitor to death.

He described growing up comfortably in the D.C. suburbs and North Jersey. He was 16 when his mother got cancer. His father became addicted to crack. The money went fast - "to poverty in a month."

After leaving college - he studied theater for a year at Manhattan Marymount on scholarship - he went off on adventures. Demolition man. Riverboat deck hand. Engine room specialist on deep-sea tankers. He followed a girlfriend to Kazakhstan, managed to put away a chunk of money, bought a house in Baltimore.

None of those travels, none of that work, ever left him as satisfied, he says, as volunteering at a tiny Baltimore organization called Tender Bridge. His job was keeping kids company in a hockey league when they got sent to the penalty box, which they called the Chill Zone. "That became my specialty."

When he moved here in February 2007, seeing Philadelphia as an inexpensive place to get paid for working with kids, he found it hard to get a job in counseling without a college degree. So he decided to start a branch of Tender Bridge in Philadelphia, funded modestly from his savings.

His specialty now is finding good things for kids to do that don't cost anything. Twice a week he takes them to Bike Works and baseball. Other days he hits Clark Park or Whole Foods with them. ("They really slam the free samples. After a few hours, we buy a bag of chips and salsa on the way out.")

I asked Bonarek what he does when he's not doing his program. He volunteers for CASA, a nonprofit that advocates in court for neglected and abused children. And he mucks out stalls a few hours a week in a Fairmount Park stable. That job pays and keeps him humble, he said.

"I see it as work therapy," he said. "If you ever start thinking you're special and better than anybody else, spend a day cleaning up animal poop. Thousands of pounds of it. Between that and the daily failures I go through taking care of kids, it keeps me pretty modest."

Sometimes things that look too good to be true turn out to be the real deal.

Daniel Rubin:

For more information visit www.TenderBridge.org/

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