Libba Cotten made up the Classic folk song "Freight Train" when she was 12. At 87, she's still singing it.

She's a great-grandmother, the center of a large and loving family and financially secure, with a home near her grandson's in Syracuse, N.Y. But Cotten isn't about to stay at home and give up performing music. She plays, she says, "as often as I'm asked.

"I don't have any hobbies," she adds. "I may cook a little bit, but music is the main thing."

Libba Cotten, who's been a quiet and deep influence on many folk singers who came to maturity in the '60s, is in Washington this weekend. She turns 87 today and friends and family are throwing a bash for her at the home of Ralph Rinzler, head of the Smithsonian's Folklife Program.

The party has been an annual event for six years. And for the last two years Cotten has come to the party from Syracuse, where she moved in 1978. Before that she had lived in Washington for 30 years.

"I was tired of being cooped up in an apartment," she says. "I was used to being in a yard with birds and flowers. My grandson Larry has a house in Syracuse. So I asked him to look for one for me."

Cotten was thrilled by the first snowfall she saw in Syracuse. "I put on my boots and walked around in it," she recalls. "I hadn't enjoyed snow like that since I was a child in North Carolina. I swept my sidewalk clean for the first two or three times it snowed. But it kept snowing. And I gave up."

Cotten speaks in a soft, lyrical voice much like she sings. Her hand gestures, like her guitar and banjo playing, are so graceful that they become natural complements.

"Freight Train" has been recorded and performed by musicians all over the world. Cotten's guitar style was described by folk singer Alice Gerard as a "synthesis of turn-of-the-century parlor music, blues, church songs and a little ragtime."

She started playing music as a child in Chapel Hill, N.C. "My brother had a five-string banjo," she says with a grin, "and I was always bothering it, freaking strings and what not. Sometimes he'd find a string broken and he'd just shake his head and say, 'Another string broken.' He never said he wished that I'd leave his banjo alone."

Eventually her brother left home, taking his banjo with him. "I missed it so much," she says, "I decided I'd try to buy my own."

So at age 11, she put on her best dress, went downtown and asked strangers if they needed someone to do housework. A women hired her at the 1904 wage of 75 cents a month. Later, she got a raise: $1 a month.

After a few months she bought a guitar, not a banjo, for $3.75. "I didn't get no rest," she says with a laugh. "I was playing on it night and day.

Wasn't too long before I joined the church. And the deacons told me to stop playing those wordly songs. Sometimes I'd forget and play them, and I'd have to catch myself and go into a church song. I give those deacons credit for helping me to learn a lot of church songs."

Cotten settled in Washington in 1948. While working at Lansburgh's Department Store during the Christmas holidays, she met composer Ruth Crawford Seeger, who offered her a job as a domestic.

Working for the Seegers opened up new musical vistas for Cotten. She hadn't played or sung in years. And the Seegers were purveyors of the American musical tradition. At the time, Peggy Seeger was learning to play guitar and picked up and adapted Cotten's styled to her own playing.

On Saturday nights the family would gather and sing. Peggy and her father, Charles Seeger, played guitars; Mike, a brother, played autoharp.

Ruth Seeger gave paino lessons and compiled a collection of folk songs for children, including some she collected from Cotten. Pete Seeger, a son by an earlier marriage and one of the country's leading folk artists, did not live with the family.

"When I went to work for the Seegers and heard all that music, I had to start playing guitar again," says Cotten. "So I got Peggy's guitar and started playing.

"Mrs. Seeger would go in her room and start her music, giving lessons, and I'd go in the other room and start mine. I'd feel so good after playing. a

"Penny, the baby child, gave me the name Libba. She couldn't say Elizabeth. She said, 'That's too hard. I'm going to call you Libba.' And from then on everybody called me Libba."

Cotten worked for the Seegers for eight years. But her association with the family didn't end when she left. In 1959, she gave her first professional performance, a joint concert with Mike Seeger at Swarthmore College. Since then she's appeared in many parts of the U.S. and several European cities.

But one of her biggest thrills was returning to Chapel Hill for a concert.

"I was just disappointed that only students showed up," she says. "None of my old friends were there. I guess most of them have moved away or died. But I'm still pushing on."