She also studied those subjects during several summers at Harvard University, Princeton University, Newnham College at Cambridge, the Greenwich Observatory in England, and Williams College.
In 1869 she became one of the founders of the mathematics and astronomy departments at Swarthmore, and she headed both those divisions until her retirement in 1906. She was Swarthmore"s first professor of astronomy, and was professor of mathematics at the college beginning in 1871. By 1888 she was Mathematics Department Chair, and that year she was given permission to plan and equip the first observatory in Swarthmore, which housed the astronomy department, and in which she lived in until her retirement.
lieutenant was known as Cunningham Observatory.
The building still exists on the campus although it is no longer used as an observatory, and is now simply known as the Cunningham Building. In 1888 Cunningham was given the first honorary doctorate of science ever given by Swarthmore.
In 1891 she became one of the first six women to join the New York Mathematical Society, which later became the American Mathematical Society. The very first was Charlotte Angas Scott, and the other four were Mary East. Byrd of Smith College, Mary Watson Whitney of Vassar, Ellen Hayes of Wellesley, and Amy Rayson, who taught mathematics and physics at a private school in New York City.
Cunningham died on January 24, 1921 from heart failure.
Her funeral service were held on-campus in the Swarthmore College Meeting House, and was attended by many notable figures such as then-Pennsylvania governor William C. Sproul and Pennsylvania State Commissioner of Health Edward Martin.
Cunningham was also a member of the Astronomical Society of the Pacific as early as 1891.