returned to Oswego Normal to write her work Studies in General History, which was published in 1885 for secondary-school students. On August 6, 1885, she married Earl Barnes, a former student, who was eleven years her junior. While Barnes taught at various universities, Sheldon concentrated on her writing and collaboration with historian Andrew Dickson White. In 1891 Barnes was appointed head of the department of education at Stanford University, where he implemented her method studies of educational history and child development. In March 1892 Sheldon joined the department of history at Stanford as the first female faculty member. As an assistant professor, she taught 19th-century European and Pacific Slope history. The couple collaborated on Studies in American History which was published in 1891 for eighth-grade students. However, Sheldon owned the copyright to the text. She also conducted research in four California school districts regarding the source method and educational philosophy, through which she designed a history curriculum that accounted for developmental changes. Sheldon would go on to publish Studies in Historical Method, which was directed towards teachers and layman historians interested in learning about historical method. In 1897, the couple resigned from Stanford to travel and write in Europe. Death and legacy Sheldon's health had always been of serious concern, and her chronic illness worsened while abroad. She underwent an unsuccessful new medical procedure to treat an organic heart disease. On August 27, 1898, she died in London. Per her request, Barnes buried her in a Protestant cemetery in Rome. Her teaching method encouraged students to "study the primary sources in an 'independent and solitary' way using her questions as guides to problem solving...in order to develop the students abilities to observe, weigh evidence, to generalize and to exercise creative historical imagination." This approach was described as progressive for the time, utilizing a case method that "hastened the improvement of more conventional history textbooks." Studies in General History incited debate among leading historians and educators. The American Historical Association's Committee of Seven issued a report in 1899, rejecting Sheldon's approach to teaching. The panel, chaired by Andrew C. McLaughlin, recommended "limited contact with a limited body of materials, an examination of which may show the child the nature of the historical process." Though largely ignored in print, her teaching philosophy, especially in relation to critical thinking for students, influenced the curricular structure of general education courses in the mid-twentieth century.