Answer by taking a quote from the following article:

Lillian Evelyn Moller Gilbreth (May 24, 1878 - January 2, 1972) was an American psychologist, industrial engineer, consultant, and educator who was an early pioneer in applying psychology to time-and-motion studies. She was described in the 1940s as "a genius in the art of living." Gilbreth, one of the first female engineers to earn a Ph.D., is considered to be the first industrial/organizational psychologist.

Gilbreth had a lifelong interest in teaching and education. As an undergraduate at the University of California, Berkeley, she took enough education courses to earn a teacher's certificate, and her doctoral dissertation at Brown University was on efficient teaching methods. While residing in Providence, Rhode Island, Gilbreth and her husband taught free, two-week-long summer schools in scientific management from 1913 to 1916. The Gilbreths also discussed teaching the Gilbreth System of time-and-motion study to members of industry, but it was not until after her husband's death in 1924 that she created a formal motion-study course. Gilbreth presented this idea at the First Prague International Management Congress in Prague on July 1924. Her first course began in January 1925. Gilbreth's classes offered to "prepare a member of an organization, who has adequate training both in scientific method and in plant problems, to take charge of Motion Study work in that organization." Coursework included laboratory projects and field trips to private firms to witness the application of scientific management. She ran a total of seven motion study courses out of her home in Montclair, New Jersey until 1930. To earn additional income to support her large family, Gilbreth delivered numerous addresses to business and industry gatherings, as well as on college and university campuses such as Harvard, Yale, Colgate, the University of Michigan, MIT, Stanford, and Purdue University. In 1925 she succeeded her husband as a visiting lecturer at Purdue, where he had been delivering annual lectures. In 1935 she became a professor of management at Purdue's School of Mechanical Engineering, and the country's first female engineering professor. She was promoted to a full professor at Purdue in 1940. Gilbreth divided her time between Purdue's departments of industrial engineering, industrial psychology, home economics, and the dean's office, where she consulted on careers for women. In cooperation with Marvin Mundel, Gilbreth established and supervised a time-and-motion-study laboratory at Purdue's School of Industrial Engineering. She also demonstrated how time-and-motion studies could be used in agricultural studies and later transferred motion-study techniques to the home economics department under the banner of "work simplification". Gilbreth retired from Purdue's faculty in 1948. After Gilbreth's retirement from Purdue, she continued to travel and deliver lectures. She also taught at several other colleges and universities, and became head of the Newark College of Engineering in 1941. Gilbreth was appointed the Knapp Visiting Professor at the University of Wisconsin's School of Engineering in 1955. She also taught at Bryn Mawr College and Rutgers University. In 1964, at the age of eighty-six, Gilbreth became resident lecturer at Massachusetts Institute of Technology. In 1968, when her health finally began to fail, Gilbreth retired from her active public life and eventually entered a nursing home. CANNOTANSWER

What did she teach?

While residing in Providence, Rhode Island, Gilbreth and her husband taught free, two-week-long summer schools in scientific management from 1913 to 1916.