Practicing kung fu, playing mahjong with villagers, singing karaoke with children, hanging out with strangers in a Chinese village they've never been to before - a group of San Franciscans feels right at home.

"It's a very moving and emotional experience for people to go back to their ancestral villages. It's a way that we can learn more about our connections to China, and at the same time learn more about our family histories," said Steven Owyang, an adviser and leader of Friends of Roots.

For nearly three decades, the San Francisco-based organization has taken about 40 such groups involving around 400 United States citizens to their ancestral villages in Guangdong province, from where many Chinese Americans have historically migrated.

Owyang, whose surname was Anglicized, is a retired administrative law judge in California. He said he still remembers his first visit to his ancestral village in Zhongshan, Guangdong, where almost everyone shares the same family name - Ouyang.

"To see pictures of my own family and relatives upon the wall in a home in some village that I've never been to before, that's very moving," he said.

"It showed me that people in China still feel very connected to their family even though the family has left the village two or three generations ago," said Owyang, whose family left Guangdong for the United States in the 1870s.

In November, he chaperoned a Roots Plus group (for people aged 30 and above and families) to Guangdong, where the 37 participants visited their ancestral villages, a martial arts school, as well as historically and culturally significant sites, such as Sun Yatsen Memorial Hall, the Overseas Chinese Museum and Canton Tower.

Another Roots Plus group returned from China last month and a Roots group (for young adults aged between 18 and 30) of 11 people will make a journey west in June, said Owyang.

"Every family has their own story about why they left China and how they got to the US. I think curiosity about that and trying to understand what it means to be a Chinese American is the main thing that draws them to the program," said Owyang, who has been involved with the program for the past 12 years.

Founded in 1991 by Chinese American historian Him Mark Lai and educator Albert Cheng, the In Search of Roots program aims to help participants - who call themselves "Rooters" - better understand their heritages and identities as Chinese Americans through research of family history and genealogy.

America's postwar prosperity fostered the growth of a Chinese American middle class of professionals, technical personnel and businesspeople, and this middle class showed an increased interest in the history and culture of the common ethnic community and the deeds of their forebears, Lai and Cheng explained in the 2002 book The Chinese in America: A History from Gold Mountain to the New Millennium.

Through a partnership with the Chinese Historical Society of America, the Chinese Culture Foundation and the Overseas Chinese Affairs Office in Guangdong, the program involves a yearlong commitment to researching one's Chinese American family history and genealogy.

After constructing a family tree and exploring related family history in America, participants explore their roots in China. Then they create an exhibit of writings, photographs and videos, and hold a presentation summing up their experience for families, friends and the community.

During the course of searching for their family heritage, the Rooters become "much more appreciative of the older generations and everything they had to go through to establish a life in the US", Owyang said.

The program has expanded from the original Pearl River Delta region to other parts of Guangdong in response to participants needs.

"The program is the first step in their quest," Owyang said. "After the program, a Rooter settled in Beijing and started a business. Another Rooter decided to stay and study Chinese at Sun Yat-sen University in Guangzhou. Two sisters are going back to their village again by themselves. They just want to keep in touch and learn more about their history in China."