This supplement is intended to present the idea behind and the characteristics of the Open School in greater detail than in the preliminary report. The Open School was conceived to meet several important needs in Wisconsin education: (1) to enable more people of all ages to enroll in formal and informal programs of education on a continuing basis; (2) to guide and accelerate the use of mediated instruction, and to provide a Statewide laboratory for testing and evaluating educational media and technology; and (3) to realize the economies and efficiencies possible through coordinated planning, program development, and Statewide media utilization and access systems. The Open School is characterized by open admissions; open communications (no walls, uses communications media only); open ideas/curricula; open access (homes, jobs, communities); open participation, accreditation, and cooperation; and open staff sharing (between regular and open schools, libraries, public and private schools, business, and industry). A related document is EA 003 570. (Author)