Portland State University (PSU) is a public state urban university located in downtown Portland, Oregon, United States. Founded in 1946, it has the largest overall enrollment of any university in the state of Oregon, including undergraduate and graduate students. It is also the only public university in the state that is located in a major metropolitan city. Portland State is part of the Oregon University System. The athletic teams are known as the Portland State Vikings with school colors of green and white. Teams compete at the NCAA Division I Level, primarily in the Big Sky Conference. Schools at PSU include the Portland State University School of Business Administration, Graduate School of Education, School of Fine and Performing Arts, School of Social Work, College of Urban and Public Affairs, Maseeh College of Engineering and Computer Science, and the College of Liberal Arts and Sciences. The University was established as the Vanport Extension Center in June 1946 to satisfy the demand for higher education in Portland for returning World War II veterans. Classes were held in the vacated-for-summer Vanport Junior High School. This first summer session had 221 students.