The study measured Mexican American secondary students' perceptions of racial/ethnic isolation in their educational environment. Utilizing the input from a committee of five adult Mexican Americans and five adult Anglo Americans, a 25-item questionnaire was constructed. Each item consisted of a statement describing a condition that may or may not exist in the students' perceived educational environment. For each statement, students were to respond to two questions: "To what degree does this condition NOW exist in your school?" and "To what extent SHOULD this condition occur in your school?" Items measured three areas of alientation--social, academic, and extracurricular. Ninety-nine questionnaires were completed by Chicano and Anglo students in secondary schools in Houston, Lockhart, McAllen, San Antonio, and Waxahachie (Texas). Analyses included a ranking of items by computing the discrepancy between the SHOULD and NOW responses. Among the findings were: of the ten top-ranking items, all but one were social or academic in nature; items dealing with positive social interactions between Mexican American, Anglo, and Black students and teachers were top ranked; verbal harassment between Mexican Americans and Anglos was identified as the number one area of isolation; and the need for schools to offer formal courses in human relations skills was identified. (NQ)