The three-story building was constructed in 1878 as a gymnasium style of school, reflecting the German heritage of the local residents.

The new building allowed the school to increase its enrollment to 103 students in its first year.

The school began admitting female students in 1930, and received accreditation as a four-year college in 1934.

Old Main now houses faculty offices, art studios and general classrooms and is listed on the National Register of Historic Places.

This article about a property in DuPage County, Illinois on the National Register of Historic Places is a stub.