This book argues for an adaptation of Forrester's urban dynamics model for evaluating the impact of desegregation on the Seattle public schools. It is suggested that the Forrester modeling scheme may be useful in the definition and the evaluation of desegregation programs in public schools. In particular, the model suggested should be useful in describing the impact of the Seattle school district's desegregation plan for the middle school on various participants in the proposed program. There is a discussion of planned social change along with several definitions of social change. A detailed description is made of the proposed plan of desegregation for the middle school by the Seattle school district. An explanation, with appropriate diagrams, is made of the mechanics involved in implementing the plan. The three variables that serve as indicators of social change in this study, students, teachers, and the black community are explained. Each variable is defined and properties of its measure are indicated. Both advantages and disadvantages of Forrester's urban dynamics model are described in the literature review. Major terms used in modeling are defined. With the use of flow diagrams, a demonstration is made indicating how this model might be used. (Author/AM)