Designed and implemented to improve the academic achievement of a predominantly Mexican American student body, this project of the Edgewood Independent School District in San Antonio, Texas, part of the Experimental Schools Program, attempted to improve the affective and cognitive environment of the students through encouraging the use of Spanish, adding culturally relevant materials to the curriculum, and enhancing pupil/teacher relationships. A study of classroom teacher behaviors initially employed very small samples of experimental and comparison students and was later expanded to larger groups to more fully document possible changes produced by the four-year program. The implementation of the program significantly changed neither the emotional climate scores nor teacher interpersonal style scores (mostly at low, positive levels), nor did it significantly raise scores for the measures above those found in the group of comparison classrooms. Measures of individualization of instruction, increasingly emphasized during the fourth year of the project, led to the tentative conclusion that training of teachers, enhanced by the appropriate materials, can bring about changes in instructional approaches. (JD)