The history of ISTA is divided into three eras. The first period deals with the defining of the Association and chronicles its quest for universal public education, and its efforts to establish professional standards and secure benefits for teachers. Although this group of educators was a loosely knit association of individuals, they were able to accomplish much. Next the Association became ""professional"" with a paid staff instead of volunteers, only to be faced with the crisis of the Great Depression. Robert H. Wyatt, a progressive educator, was selected to lead this organization as the depression ended, and he embraced education as a means for social change. Wyatt persistently lobbled legislators for increased funding, which included federal aid for education, although it was a radical idea at the time. Under his direction, ISTA soon became a powerful lobbying group. The final period looks at the Association as it was transformed into a union while still maintaining its success as a lobbying organization. Various issues were paramount during this period - unification, collective bargaining, rebuilding and refocusing.
On Christmas Day in 1854, teachers and advocates of education came together to form the Indiana State Teachers Association. At that time, many Hoosiers did not embrace the concept of ""free education,"" instead believing that schools ought to be funded by those who were being educated. Immediately after ISTA's founding, its members began their advocacy of education, especially free public education for all children. Over the next 150 years, members of the Association stood ready to advance the cause of education.