Katharine Q. Seelye in The New York Times

When Bernice Sandler was a schoolgirl in the 1930s and ’40s, she was annoyed that she was not allowed to do things that boys could do, like be a crossing guard, fill the inkwells or operate the slide projector.

When she was older, teaching part-time at the University of Maryland, she was told that she wasn’t being hired for a full-time job because “you come on too strong for a woman.” Another interviewer complained that women stayed home when their children were sick. Another rejected her by saying that she was “just a housewife who went back to school.”

By that time, which was 1969, Dr. Sandler was more than annoyed. She was good and mad. And that led her to become the driving force behind the creation of Title IX, the sweeping civil rights law of 1972 that barred sex discrimination by educational institutions that received federal funding.

Dr. Sandler, who died on Saturday at 90, was known as “the godmother of Title IX.” She was central to its development, passage and implementation.

“Every woman who has gone to college, gotten a law degree or a medical degree, was able to take shop instead of home-ec, or went to a military academy really owes her a huge debt,” Margaret Dunkle, a research colleague and friend, said in a telephone interview.

As time went on, Dr. Sandler identified more areas where sexual discrimination could be fought with Title IX. One was college athletics. It has since been transformed, with far more women able to play sports today than in the past.

Another focus was sexual assault and harassment. The United States Supreme Court has established that sexual harassment of students qualifies as discrimination in violation of Title IX; schools that receive federal funding must take steps to prevent sexual misconduct on their campuses.

“Title IX turned out to be the legislative equivalent of a Swiss Army knife,” Marty Langelan, an expert in sexual harassment and longtime friend of Dr. Sandler’s, said in a telephone interview.

Back in the 1960s, Dr. Sandler did not consider herself a feminist. It was her husband who defined her rejection notices as sex discrimination.

“Like many women at that time,” she wrote in a 1997 article for the National Association for Women in Education, “I was somewhat ambivalent about the women’s movement and halfway believed the press descriptions of its supporters as ‘abrasive,’ ‘man-hating,’ ‘radical,’ and ‘unfeminine.’ ”

Dr. Sandler delved into research on sex discrimination, which at the time was not illegal in education. In a footnote to a scholarly article on enforcing civil rights legislation, she found a golden nugget — a reference to an unheralded executive order, amended by President Lyndon B. Johnson, that barred organizations with federal contracts from discriminating on the basis of sex.

Dr. Sandler well knew that most universities received federal dollars.

Armed with that executive order, she and the Women’s Equity Action League, a now-defunct spinoff of the National Organization for Women that focused on equality for women in employment, began a historic class action in 1970 on behalf of all women in higher education.

They did not go to court but instead filed an administrative complaint with the Labor Department against all colleges and universities in the country, charging an “industrywide pattern” of discrimination against women in academia. They sought an investigation into admission quotas to undergraduate and graduate schools and into faculty hiring practices, promotions and salary differentials.

Dr. Sandler vacuumed up data on rampant discrimination, attaching 80 pages of documentation to the complaint. She pointed out quotas, like one at the Cornell School of Veterinary Medicine, which admitted two women a year, regardless of how many applied. She found that many academic departments across the country had no women faculty at all and that women were often denied scholarships if they were married.

Dr. Sandler shared all of her research with Rep. Edith Green, an Oregon Democrat, who held seven days of hearings in the House of Representatives in the summer of 1970 on sex discrimination in education; after the hearings, Ms. Green hired Dr. Sandler to join her subcommittee staff to put together the written record of the hearings.

That record became the basis for the legislation that eventually became Title IX. Senator Birch Bayh, an Indiana Democrat, pushed the bill through the Senate, and President Richard M. Nixon signed it into law.

“She had many allies, but Bunny Sandler was the point person,” Ms. Langelan said. “She taught us that you could actually do something about discrimination.”

Dr. Sandler said later that she had been naïve in guessing how quickly change would come. She initially thought, she said, that “it would only take a year or two for all the inequities based on sex to be eliminated.”

Over time, she kept lengthening that prediction, until, she said, she finally realized that true change “would take more than my lifetime to accomplish.”

Her daughter Deborah Jo Sandler said Dr. Sandler died of cancer at her home in Washington, D.C. Dr. Sandler is also survived by another daughter, Emily Maud Sanders, and three grandchildren.

She received a bachelor’s degree in psychology from Brooklyn College in 1948, a master’s in psychology from the City College of New York in 1950, and a doctorate in education from the University of Maryland in 1969. Her marriage in 1952 to Jerrold Sandler ended in divorce in 1978.

Unable to find a job in psychology or counseling, Dr. Sandler worked as a preschool teacher, a guitar instructor and a secretary.

But once she got involved in Title IX, she devoted the rest of her life to combating sex discrimination. She spent two decades as the director of the Project on the Status and Education of Women at the Association of American Colleges. She delivered more than 2,500 presentations and served as a consultant to numerous institutions, including the Citadel, the South Carolina military college, as it edged toward coeducation with a “female assimilation plan.”

When attending events at the all-male Cosmos Club, an exclusive Washington organization that did not admit women until 1988, Dr. Sandler refused to enter by the back door, as women were instructed to do. Once, while scattering buttons around the club that said “Uppity Women Unite,” a male waiter asked for a handful. He then planted them on the urinals in the men’s bathrooms.

Dr. Sandler received multiple awards, a dozen honorary degrees and was inducted into the National Women’s Hall of Fame in 2013.

In a 2007 article, she concluded that Title IX had precipitated a social revolution comparable to the Industrial Revolution. Women and men, she said, “are far closer to equal than they have ever been in the history of the world.”

But, Dr. Sandler added, “We have only taken the very first steps of what will be a very long journey.”

Photo credit: McClatchy-Tribune/Alamy