In 1938, Chulalongkorn University's Preparatory School was founded to provide pre-collegiate education to students. Those who managed to enter the university had to spend two years in the Preparatory School before going on to the Faculty of Arts and Sciences. The Preparatory School, however, ceased to be a university-owned preparatory school in 1947 and became the independent Triam Udom Suksa School. Later, the university established Chulalongkorn University Demonstration School (CUD) as a laboratory school for primary and secondary education for the Faculty of Education.