In the colonial period in America, the only requirements for teaching in the lower schools were a modicum of learning and a willingness to work in what was then an ill-paid, low-prestige occupation. By the 1820s and 30s, however, teacher training became common in the academies, the equivalent of today's secondary schools. Many women, excluded from men's preparatory schools, could obtain an education only in such academies. The nation's first private normal school, a two-year post–high school training institute for elementary-school teachers, was opened by Samuel R. Hall (1823); the first state-supported normal school was created by Massachusetts (1839).
With the assistance of Henry Barnard and Horace Mann, the number of normal schools in the United States increased rapidly during the latter half of the 19th cent. Since their sole purpose was professional instruction of elementary-school teachers, an especially strong emphasis was placed on the psychology of child development. Preparation for secondary-school teaching, which demanded a larger academic component, was still left to liberal arts colleges. Nevertheless, by the turn of the century many normal schools had expanded into four-year degree-granting teachers colleges, and by the 1920s and 30s these teachers colleges, generally supported by the public, were training substantial numbers of the nation's public-school teachers.
Training for secondary-school teachers remained primarily a function of liberal-arts colleges until after World War II, when growing numbers of students, a strong rise in the average age of leaving school, and the growing need for technical skills in the nation's workforce led to a demand for secondary education that traditional colleges could not meet. Since 1945, consequently, most teachers colleges have expanded their educational missions and become liberal-arts colleges offering a broad general education in addition to specialized courses in pedagogy.
In the United States, the first graduate program in education was established at New York Univ. (1887). In the following year the teacher-training school that is presently known as Teachers College, Columbia Univ., was founded. Since the establishment of those two institutions, graduate study in education has expanded rapidly.