After college, Speer taught at
Sweet Briar College, and served as secretary to British suffragist
Maude Royden while she toured in the United States. The Presbyterian Mission Board assigned her to teach English at the Women's College of Yenching University in 1925. She became dean of the college in 1934, took a furlough in 1937, and stayed at Yenching until 1941, when her job ended among the increased tensions of
World War II. She reached home in 1943, after some time in a Japanese-run internment camp for enemy aliens in China. Back in the United States, she was a popular speaker at church women's events. She became headmistress of the Shipley School, a nonsectarian girls' boarding school in
Bryn Mawr, Pennsylvania, in 1944. During her tenure, the school began enrolling African-American and Jewish students. She retired in 1965. In 1979 she traveled to Yenching University with a group of American students. Speer was president of the Headmistresses Association of the East (1950 to 1952), the National Association of Principals for Girls (1959 to 1961), and the
Lower Merion Township Human Relations Council (1966 to 1968). She served on the session of the
Bryn Mawr Presbyterian Church. == Personal life ==