America were not allowed in physics laboratories, Ladd chose to study mathematics. Later in her life, Ladd would reflect on her decision and say, "had it not been for the impossibility, in those days, in the case of women, of obtaining access to laboratory facilities" she would have eagerly gone on to study physics. In 1887 Vassar College awarded Ladd an honorary LL.D. Early career After graduating, Ladd taught science and mathematics at secondary level in Washington, Pennsylvania; Hollidaysburg, Pennsylvania; Massachusetts; and New York for nine years, although her diary entries indicate that her interest in teaching diminished over time. During this time, she contributed seventy-seven mathematical problems and solutions to the Educational Times of London. She also published six items in The Analyst: A Journal of Pure and Applied Mathematics and three in the American Journal of Mathematics. Graduate education In 1878, Ladd was accepted into Johns Hopkins University with the help of James J. Sylvester, an English mathematician among the university's faculty who remembered some of Ladd's earlier works in the Educational Times. Ladd's application for a fellowship was signed "C. Ladd", and the university offered it to her without realizing she was a woman. When they did realize this, the board tried to revoke the offer, but Sylvester insisted that Ladd should be his student, and so she was. She held a fellowship at Johns Hopkins University for three years, but the trustees did not allow her name to be printed in circulars with those of other fellows, for fear of setting a precedent. Furthermore, dissension over her continued presence forced one of the original trustees to resign. Since the university did not approve of coeducation, at first Ladd was only allowed to attend classes taught by Sylvester. However, after displaying exceptional work in his courses, Ladd was allowed to take courses with additional professors. Even though she was awarded a stipend, she was not allowed to have the title of "fellow". During 1879 and 1880, Ladd took classes taught by Charles Sanders Peirce, who has been called the first American experimental psychologist. She wrote a dissertation "On the Algebra of Logic" with Peirce as her thesis advisor. The dissertation was published in Studies in Logic (C.S. Peirce, ed.) in 1883. In 1884 Ladd attended William Thomson, 1st Baron Kelvin's master class and met her future husband, Fabian Franklin. Due to her studies with Sylvester and Peirce,