Born in Latrobe, Pennsylvania, she studied psychology at the University of Pittsburgh and met her husband, Gerald Gardner, whom she married the same year she received her bachelor's degree.

The couple moved to Dublin, Ireland, but returned to Pittsburgh after five years, where Evansgardner received a doctorate in experimental psychology.

[2] Shortly after they married, the couple spent five years in Dublin, Ireland, where Evansgardner resisted her role as a housewife.

She was frustrated that women were diagnosed with mental disorders if they expressed anger or depression about receiving unfair treatment as the result of their gender.

There were only twelve women who served as symposium chairs or gave addresses at the 1965 annual meeting of the American Psychological Association (APA), out of a total of 1700 speakers.

[8][9] In 1969, Evansgardner founded the Association for Women in Psychology (AWPA) with thirty-five other psychologists and served as the first interim president.

[12] Evansgardner was active in the civil rights movement, joining the National Association for the Advancement of Colored People (NAACP) with her husband in 1963.

[5][15] They printed speeches and articles from feminists and other NOW members, including "The Tyranny of Structurelessness" by Jo Freeman and I'm Running Away from Home, But I'm Not Allowed to Cross the Street by Gabrielle Burton.

Evansgardner and Gardner hosted weekly letter-writing parties in their home to write legislators on their and their friends' behalf between 1969 and 1978.

[6][23] The Commission upheld the complaint filed by First Pittsburgh NOW and the newspaper lodged a court case, arguing that this decision infringed on its right to freedom of the press under the First Amendment.

[14] She coordinated demonstrations across fifteen cities in New York, Massachusetts, Minnesota, Florida, Washington, Pennsylvania, Illinois, Alabama, Ohio, Missouri, New Mexico, Texas, and California.

[27] She was also involved in the landmark lawsuit against the company which began in November 1970 led by the Equal Employment Opportunity Commission alleging racial and sexual discrimination.

[29] She worked with Heide, Patricia Hill Burnett, and Rona Fields on an international conference that was held on June 1, 1973, bringing together more than 300 women from 27 countries.

[2] On February 17, 1970, she was among a group of Pittsburgh NOW chapter members who disrupted a hearing on lowering the voting age to eighteen, holding up signs and demanding that the Senate act on the Equal Rights Amendment (ERA).

[31] She also interrupted a hearing on the nomination of G. Harrold Carswell to the United States Supreme Court and was instructed by Senator Edward Kennedy to sit down.

In 1972, she was arrested alongside her husband for assisting in the effort to place a paper-mâché of Susan B. Anthony on the head of a statue of Father Duffy in Times Square.

"[2][5] Evansgardner and Jeanne Clark went to Washington, D.C. in 1975 to protest in favor of reproductive rights at the Vatican embassy, where a man was arrested for spitting at her after she kicked him.

Justice John Paul Stevens wrote in the decision that allowing appeals would harm the final judgment rule.

[38] She ran on a platform of amending building codes to allow for prefabricated houses and sharing the city tax burden with people who commuted into Pittsburgh from the suburbs.

[39] Evansgardner was invited to participate in several talk shows and candidate forums, where she used the opportunity to discuss feminist issues and distribute brochures on the ERA.

[43] She presented a paper at the National Women's Studies Association annual meeting in June 1985, where she argued that the word 'feminism' should be replaced with 'isocracism', implying equality of power.