Mary Petty grew up in a Quaker community known as Bush Hill outside of Greensboro, NC. She received her bachelor’s degree from Wellesley in 1885, and taught briefly at Guilford College (also in Greensboro) before coming to the State Normal and Industrial School in 1893. She led the department of chemistry there from 1893 to 1934. In addition to her classroom teaching, she helped lead the campus’s Science Club, an organization for faculty members and advanced students to explore areas not included in the formal coursework.
Petty was also very active in the Greensboro community. She served as president of the Greensboro Woman’s Club and the Friday Afternoon Club, and as secretary of the State Federation of Women’s Clubs. She was also the first woman to serve on the Board of Trustees of Guilford College.
In 1960, the science building on campus (originally constructed in 1940) was renamed in her honor and continues to be known as the Petty Building.