Four case studies conducted by the Mid-continent Regional Educational Laboratory (McREL) Rural Education Project examined four clusters of rural schools and their efforts to improve schooling by collaborating and sharing resources. The Mid-Missouri Small School Consortium involved five rural school districts in efforts to incorporate microcomputers into school operations and curriculum and was distinctive in its use of the consortium concept to provide teacher in-service training. Contract Vocational Education: The Missouri Model evolved from a study of dropouts in three south central Missouri counties into a community-business-school cooperative program to provide rural students with vocational skills needed in their communities. The South Dakota Small Schools Cluster involved six small school systems, McREL, and South Dakota State University in an effort to assist small schools in maintaining quality education at affordable prices when consolidation was not viable. Project Innovative Curriculum brought together four schools in south central Nebraska to concentrate on cooperative curriculum development, increase exchange of ideas among teachers, and encourage resource sharing. Each case study provides descriptions of schools and communities, problems which prompted the cluster's formation, cluster development and activities, program evaluation, conclusions about successful clusters and suggestions for implementation of the cluster approach. (LFL)