James Pillans invented blackboard in 1800s. He worked as the headmaster of the Old High School of Edinburgh, Scotland. This slate had wooden frames to protect them from breaking. The earliest blackboards were simply small pieces of slate. In place of chalk, students would use another piece of slate to write on the board. Written remarks would be erased with the use of a rag in order for the student to work on the next lesson. James Pillans took slates and hung them on the wall to teach them Geography and this brought him an idea of the blackboard. Mr. George Baron, a Maths teacher carried this idea to the United States in 1801. He gave maths presentations on the blackboard in the West Point Military Academy, a place where he taught. The idea got popular among the teachers as it saved time, enhanced understanding and helped cater a larger group at the same time.
Soon the blackboard production started in Maine, Maryland, Virginia, Vermont and New York and was supplied all over America. The blackboard became a common teaching aid for all the schools. And since then blackboards are part and parcel of all the classrooms all over the world. This invention brought revolution in the field of education.