Students at 19 Michigan elementary schools in 17 districts showed a dramatic improvement in Michigan Educational Assessment Program test score results from 1976 to 1979. A three-pronged effort to identify the factors associated with the improvement involved a computer analysis of school demographic data, field interviews, and a symposium of 107 key personnel from 18 of the 19 schools who corroborated the field interviews. Analysis of the demographic data failed to reveal any positive correlation with success; however, a "Formula for Success" extracted from the interviews and symposium contains seven elements that constitute a "critical mass" that all 19 schools possess. The seven elements are: (1) the staff has a high degree of intercommunication; (2) the instructional program contains the basic elements of mastery learning; (3) the principal is a strong leader with an understanding of curriculum and instruction; (4) the staff is stable, flexible, innovative, and skilled; (5) the parents are supportive because the school communicates well with them, and in some cases community education programs make this possible; (6) the superintendent is a leader who communicates clearly the importance of academic achievement; and (7) all the parties involved in the teaching-learning process know what is expected of them. (MLF)