Wisconsin attained territorial status in 1839 and since that time public education has been a three-tier organization - - from the Department of Public Instruction to some intermediate form and finally down to the local school district. In Wisconsin and in 43 other states, some type of intermediate educational service agency serves as that "middle conduit" between the Department of Public Instruction and local school district. Wisconsin created its own unique answer through the formation of the Cooperative Educational Service Agencies (CESAs) in 1964. 

Cooperative Educational Service Agencies were created in 1964 in response to the needs of the local school districts for a provider of cooperative services that the individual districts could not obtain or afford or economically provide by themselves.

CESA 5 is one of twelve cooperatives operating in Wisconsin. CESA 5 is governed by an 11 member Board of Control with members from participating school boards, and provides services to 35 school districts.

The Portage Project, administered by CESA 5 and initially funded in 1969 by the Bureau of Education for the Handicapped, continues to provide training, develop exemplar materials, and assist in developing models for high quality direct services to young children and their families. The project has gained a great deal of recognition throughout the country, and internationally, for the training and materials developed by project staff and some materials have been translated in 40+ languages for use around the world.