Greenfair “Brother” Moses III teaches basketball skills to children in the gym of the Langley Park Boys and Girls Club, where he has volunteered for 20 years. (Dan Gross/THE GAZETTE)

Next month, Greenfair “Brother” Moses III will portray a child in his new theater production of “1001 Black Inventions The Musical.” Most other days, he plays the role of father and mentor at the Langley Park Boys and Girls Club in Hyattsville.

Moses, 63, spends six days a week at the club on Merrimac Drive, where he has volunteered for 20 years. He and his wife, Julie, have run the organization for the past decade.

He is also a writer, producer and performer. For more than 40 years, he has portrayed the Rev. Martin Luther King Jr., giving King’s speeches in cities around the world.

On Aug. 9, he’ll combine his two passions. His theater company, QuietFire Productions, will present “1001 Black Inventions The Musical” at the Bowie Performing Arts Center.

Moses said profits from the production will go toward improving the Langley Park Boys and Girls Club’s facility, specifically the building of a fence.

Moses created the musical adaptation of the “1001 Black Inventions” play, written by Ersky Freeman. Moses had previously acted in the play, about families attempting to live in a world without African American inventors.

“This whole thing talks about positive things that young black males and their predecessors have done,” said Andy Evans, a lead actor for the musical and longtime friend of Moses.

Moses said he started working at the club in 1991 as a 41-year-old intern to earn course credit at the University of Maryland.

Moses estimates that he and his wife have given more than $100,000 to the club, at one point taking out a second mortgage to keep it running. Additional money comes from donations, small membership fees and organizations that rent the club’s building for events.

Dejah McNeill, who attends Lenoir Community College in North Carolina, described Moses as “loving and kind.”

They met two years ago at High Point High School, where Moses coaches junior varsity boys basketball. McNeill, then a senior, would play basketball in the school gym. She said she considers Moses a mentor.

Tene Young of Silver Spring, whose 15-year-old son, Diallo, attends the club, said Moses was “very open and giving” to the children, sometimes paying for their meals.

“A lot of parents are not around, and he looks out for those kids,” Young said.

Moses said his theater career started when he was 16 after he launched the Quiet Fire Repertory Company with his neighborhood friends. A year later, he discovered he could impersonate King’s voice, and soon he was reenacting King’s speeches across the country.

Moses’s performing career has moved in various directions since he broke through as a performer in the late 1960s, but his dedication to children has remained a constant.

“He’s tried things on a personal level with his performing arts, but he’s never abandoned working with the youth,” Evans said.