"Get away from me with that camera. This is serious stuff." (Bill Littlefield/Only A Game)

The One Nation Tournament in Concord, Mass. brings middle school lacrosse players from New York and Boston’s suburbs together. (Bill Littlefield/Only A Game)

“There are many stories that have built up over the years of kids being asked questions in Harlem as they carry the lacrosse stick on the subway, including, ‘What is that thing? A fishing pole?’ ”

Charles Gildehaus, a board member of an organization called Harlem Lacrosse and Leadership, is one of the people responsible for children in Harlem mystifying their friends on the subway. Gildehaus, who is also president of the youth lacrosse organization in Concord, Mass., where he and his family live, spoke with me on a recent Sunday afternoon on the lacrosse field at Lincoln-Sudbury Regional High School. There, sixth-, seventh- and eighth-grade boys from Concord and some of Boston’s other western suburbs had formed teams with players from Harlem’s Frederick Douglass Academy.

"Jack, take your fingers out of your mouth. No, the other Jack." (Bill Littlefield/Only A Game)

The Harlem and Massachusetts players were teammates for a day. (Bill Littlefield/Only A Game)

“Because we’ve done this trip four years in a row, the word ‘Concord,’ they tell me, down in the schools, is almost a mythical word … that you get to go on the Concord trip this year,” he said. “And the teachers have told me that whenever they need to get the attention of the kids in class, they say one word: Concord. And there’s silence. Everyone looks around.”

“Concord” may have mythical implications now, but according to Gildehaus’ wife Pamela, a driving force in the event they call The One Nation Tournament, at first the trip just seemed scary.

“We picked the kids up,” she remembered. “They arrived in Concord in the pitch black, and they got off the bus, and everyone was quiet and shy, and very fearful. And we put them in our car, and this one boy looked out the window at all the trees and said, ‘Oh, my gosh, are there wolves in these forests?’ And then I pulled the car into the garage, and another one said, ‘You put the car right in the house?’ ”

During her first experience hosting the boys from New York, Pamela Gildehaus and her husband took in 12 lacrosse players. Ms. Gildehaus became concerned about the only one of the dozen who wasn’t active and loud.

“This one boy was sitting very quietly in a chair, reading a book. And I said, ‘Are you okay?’ And he said, ‘No, I’m just in the middle of a really great book.’ And my daughter, who was 11 at the time, said, ‘Oh, my gosh, I’m reading the same book.’ ”

Thus did the hosts and the visitors begin learning they had more in common than enthusiasm for lacrosse. And according to Charles Gildehaus, the program, which includes mentoring and academic tutoring, has helped generate better grades, higher test scores and improved self-discipline among the students from New York, some of whom he characterized as “at risk.”

On the field on that wet and windy Sunday, Andrew, a Wellesley, Mass., resident who said he’d been playing lacrosse for six years, was praising the skills of a New Yorker named Elijah and his friends, who’d first picked up sticks just a couple of months ago.

"I'm ready whenever somebody turns on the lights." (Bill Littlefield/Only A Game)

Massachusetts middle schoolers have also traveled to Harlem to play. (Bill Littlefield/Only A Game)

“I mean, they’re doing amazing,” Andrew said. “If I had to guess, if I didn’t know how long they’ve been playing, I’d guess a few years. I mean, they’re amazing.”

Two fields over, a youngster named Jordan who lived in the Bronx had taken a break from the game, just to look around.

“Well, it’s really nice,” he said. “Very quiet, um, has beautiful land, like nice, tall trees and all that.”

Jordan hadn’t been playing lacrosse for long, but he’d already been encouraged to see the game as an opportunity.

“I plan to go to high school and play it, so that I can get an opportunity for college, or something like that, or get a professional career in it.”

The children from Harlem and the Bronx are not the only players who’ve experienced “away games.” Some of the Massachusetts players have traveled by van to the Frederick Douglass Academy in Harlem, where, according to Pamela Gildehaus, “their eyes got as big as saucers.”

“The whole experience was just eye-opening for everybody, a lot of the chaperones, too,” she said. “They pulled into the FDA school, and the big gates locked behind them, and they were met with a very warm welcome.”

The One Nation Tournament is an annual event. The contact between the lacrosse players in Massachusetts and those in New York is necessarily fleeting. Though the program has raised considerable scholarship money for the students at the Frederick Douglass Academy, it may be that its most significant achievement is impossible to quantify. Pamela Gildehaus talked about that achievement as the lacrosse games went on around us, and the wind tried to scatter her words.

“They really find a spot in our hearts,” she said. “Some of them have a fabulous mom and fabulous dad and they’re really supported, but some of them have more complicated lives, and they’re really happy to meet people and make new friends and people who care about them.”