The murmur of a creek was the only sound one recent morning in a woodland clearing in Gladwyne.
Then a stream of small visitors spilled off a yellow school bus, and the Riverbend Environmental Education Center echoed with noisy energy.
The children turned over rocks, looking for brown crayfish and black mayflies in Saw Mill Run.
"I got it. I found a bug," one youngster yelled, tipping a mayfly into a basin of creek water.
Since 1974, the nonprofit Riverbend has made a science of creating fun for children by providing hands-on experiences in a natural setting. Now it is reaching out to suburban and inner-city children in a way that experts say will encourage them to learn.
The center has formed a partnership with J.K. Gotwals, Whitehall and W.S. Hancock Elementary Schools in Norristown and Dr. Tanner G. Duckrey School in North Philadelphia.
Arthur Mitchell, science coordinator for the Norristown Area School District, addressed a cocktail party for educators and supporters of Riverbend on May 2. The event introduced the program to community members.
"We want our students to experience science, not just read about it," Mitchell told the gathering at a Bryn Mawr mansion. "You can't really develop an appreciation for nature by watching the Discovery Channel."
Duckrey principal David E. Baugh said his school, at 1501 W. Diamond St., had pupils who are "99 percent African American and 96.9 percent below poverty level."
Their world, Baugh said, is frequently too dangerous for kids to go out and play.
At the same time, Duckrey is hard-pressed to provide experiences that will put them on a par with the middle-class adults they will meet later in life. Riverbend programs help chip away that cultural divide.
"We want our kids to know what it feels like to have [stream] water flow over their feet," Baugh said.
The first of 300 third graders from Norristown arrived for daylong activities at the Riverbend Center on Wednesday. The pilot program will continue this month by bringing in 45 seventh graders from Duckrey.
As part of the protocol, the students and their teachers are briefed on what to expect.
And later there's a lesson on what the children saw, and a science unit on stream studies once students are back in class, Mitchell said.
The cost of the $10,000 program is borne by corporate, individual and foundation donors.
The learning center consists of a renovated barn and two miles of hiking trails on 30 acres of meadows and woods at the northern end of Spring Mill Road in Lower Merion Township. The land encompasses the Saw Mill Run watershed, which drains into the Schuylkill.
One of the center's aims is to teach children about the watershed, said Stacy Carr-Poole, Riverbend's education director. Once kids grasp how flowing water changes the habitat that it traverses, they might be moved to respect and conserve nature in the future, she said.
The impetus for sending children back to nature isn't just coming from the local level; there's a federal push, too.
In a speech in October, Secretary of the Interior Dirk Kempthorne warned that American children have lost the traditional connection with nature.
"Healthy children are becoming unhealthy as they grow older because no one has taken them out to the woods, the rivers and the mountains," he told the National Parks and Recreation Association in Seattle.
Lack of fresh air and exercise has serious health effects, experts have said. One in five children is overweight, and some as young as 7 are at high risk of contracting diabetes.
"We as a nation must do something about this," Kempthorne told the park officials.
Jenny Morgenthau, executive director of the Fresh Air Fund, has. The New York-based group sends youngsters from the inner city for two-week vacations in the country. She has seen what fresh air can do.
"Just playing outside is good for kids. It lets them be kids," she said. "A lot of these kids go to schools without a gym or physical fitness program."
Just thinking about going to Riverbend this month has galvanized those at the three schools in Norristown.
"It's added a lot of excitement to the schools. The teachers are energized," Mitchell said.
The Riverbend Environmental Education Center is at 1905 Spring Mill Rd., Gladwyne. For more information, call 610-527-5234.