Distinct multiple regression models are discussed, along with issues and problems related to their application to the practical problem of identifying effective schools. Statistical results obtained from the application of each model are discussed. The first model was implemented in 1984, and the second in 1992. In 1984, it was decided to identify effective schools in terms of student achievement in the basic areas of reading, mathematics, and language usage. The emphasis was on standardized test scores. In 1992-93, the outcomes used for effectiveness indices include: (1) a nationally normed standardized test; (2) a state-mandated criterion referenced test with a writing sample; (3) 143 separate course-related criterion-referenced tests; (4) student promotion rate; (5) student graduation rate; (6) attendance rate; and (7) percentage of students taking the Scholastic Aptitude Test and average scores. In 1993-94, additional indices will be added. The effectiveness indices are an important part of the three-tier system of accountability being implemented in the Dallas (Texas) public schools. One table and one figure present analysis results. A 55-item list of references is included. Also provided is a description of the school performance improvement awards, a financial awards plan for effective schools. (SLD)