The topic is "free play," so it sounds mild enough, but Darell Hammond's message is strong.

Hammond, founder of an organization that helps communities build playgrounds, was 24 when he moved to Washington, D.C., in August and read a story in The Washington Post about two children who had suffocated in an abandoned car. They were looking for someplace to play.

He was so upset that he became an activist for outdoor play, creating a massive organization of volunteers that has built 2,300 playgrounds nationwide. His book, "KaBOOM!: A Movement to Save Play" became a New York Times best-seller.

This fall, the Community Coalition for Children, a local organization that strives to improve the lives of children in eastern Connecticut, will bring Hammond to New London to speak. The presentation, at 7 p.m. on Oct. 20 at the Garde Arts Center, is free and open to the public.

"He talks about his motivation and how he made this happen," said Cara Westcott, vice president of behavioral health services for United Community & Family Services in Norwich and this year's chairwoman of the Community Coalition.

Hammond said Monday in an email that he accepted the coalition's invitation to speak in New London because he wants to spread his message.

"Play has the power to benefit the whole child - mentally, physically and socially - and transform communities," he wrote. "Our message is about getting audiences to truly understand the power of play and become inspired to take action to protect and promote it."

After the community presentation, Hammond will speak to 200 to 300 middle and high school students from the area who will gather from 9:30 a.m. until 12:30 p.m. on Oct. 21 at Connecticut College, along with teachers and other adults who deal with children. The students will listen to Hammond's presentation, then meet in smaller groups to discuss what they've learned and "predesign" a playground.

Schools in Groton, New London, Norwich, Montville and Salem, along with Norwich Free Academy, Norwich Technical High School, Ella T. Grasso Southeastern Technical High School and Pine Point School in Stonington are expected to participate.

Hammond hopes that after he leaves, the community will take action by building a playground, spreading the word about the importance of play, or making sure children in their own lives get enough free play.

Westcott said Hammond's message is consistent with the coalition's mission: To create, sponsor and endorse educational and social programs "to help children thrive." Hammond also shows how one person can make a difference, which the coalition wants to impress upon people, Westcott said.

The Coalition for Children has been trying to do as much for 18 years; it was established in 1996, after a group of concerned parents and others who work with youth began meeting to see if they could have an impact. Since then, they've been sponsoring authors who speak in southeastern Connecticut and share ideas about how to make young people's lives better.

Coalition member Kathleen O'Beirne said the group also wants to be a resource for local and national grass-roots organizations about how to get started and stay organized.

"Part of our role is we also want to serve as the catalyst for other kinds of activities," she said. "We can't do it all. But we'd love to be the place that people can go to."

Last year, the coalition brought in Dr. David Katz, the director of Yale University's Prevention Research Center and co-author of "Stealth Health: How To Sneak Age-defying, Disease-fighting Habits Into Your Life Without Really Trying." Katz also helped create a system that scores food on a scale of 1 to 100 based on its nutritional value.

O'Beirne said families that had to stretch their money found his presentation particularly helpful, because they realized they could have "great nutrition in spite of economics."

The message reached a younger audience as well, she said.

The morning after Katz spoke, students meeting in small groups returned with a consensus.

"One of the things that every group said was, 'We want to have a salad bar in our cafeteria,'" O'Beirne said. The adults were pleasantly surprised. "Everyone in the whole place said, 'No way.'"

d.straszheim@theday.com