Helen Lydia "Tumbi" Frank Sheingorn, 86, an economist, teacher and volunteer with Common Cause for more than 25 years, died of an intracerebral hemorrhage July 28 at Suburban Hospital in Bethesda. She was a District resident.

A witty puzzle-solver, poet and writer, Mrs. Sheingorn had poems published in the New York Times and Cats magazine. She won The Washington Post's "Style Invitational" contest in April 1994 after offering this "really bad excuse for a moral lapse: You are not guilty of DUI if you thought someone else was driving."

That pithiness was displayed again in an October 1994 letter to the editor of The Post, in which she noted: "Rep. Newt Gingrich firmly advises political action committees to make campaign contributions to Republican candidates during the last weeks of the campaign, rather than to wait until after the election when 'access' to the victors will be more difficult and costly. Why doesn't Rep. Gingrich just tell them: Buy now and save?"

Mrs. Sheingorn, an athletic and energetic woman, worked tirelessly at Common Cause in Washington beginning in the 1970s for campaign finance reform and other causes.

Always wanting to learn more, she took a variety of classes through the Institute for Learning in Retirement and the Writer's Center in Bethesda. She was an enthusiastic reader and was in the middle of Bill Bryson's "A Short History of Nearly Everything" at the time of her death.

Mrs. Sheingorn was born in New York and grew up in Brooklyn. She graduated from Cornell University in Ithaca, N.Y., in 1939 and was Phi Beta Kappa in her junior and senior years. She received a master's degree in economics in 1941 from Bryn Mawr College in Pennsylvania.

Shortly afterward, she moved to the District and worked for the antitrust division of the U.S. Department of Justice in a job she held until 1949, when she resigned to be a stay-at-home mother. She worked part time at the Americanization School downtown, teaching English to foreign-born residents.

She took up golf in the 1960s and was seen regularly at Rock Creek Golf Course from the early 1960s to the mid-1980s. The strength of her game lay in the fact that she had a graceful swing and always hit the ball straight, her family said. She usually shot about 100.

In the 1970s, after her children were grown, Mrs. Sheingorn worked as a receptionist and assistant in her husband's dental office until he retired in 1978.

A huge fan of Dixieland jazz, Mrs. Sheingorn could be found at Colonel Brooks's Tavern on Tuesday nights listening to the Federal Jazz Commission band with good friends from the Potomac River Jazz Club. She traveled the country on jazz vacations and took several jazz cruises. She also listened without fail to "Hot Jazz Saturday Night" on WAMU (88.5 FM).

In June 2004, she had a bout of appendicitis and was treated at Sibley Memorial Hospital. After her stay there, she became a volunteer and took blood pressure for walk-ins on onday mornings.

A disciplined, avid swimmer, she was a member for 21 years of the Bethesda-Chevy Chase YMCA, where she was known for her excellent form. She would swim a half-mile four or five days a week. She loved that part of her day and was swimming when she was stricken with the brain hemorrhage that ended her life.

Her husband of 44 years, Abe Sheingorn, died in 1989. A son, Larry A. Sheingorn, died May 6.

Survivors include a son, Dr. William L. Sheingorn of Washington.