A rationale and methodology for the use of student perceptions in educational decision making, and specifically in the area of curriculum, are presented. Four sections of the paper present ways in which student perceptions may be used: to describe and compare school environments, to compare perceptions of student subgroups within the same environment, and to explore relationships between the behavior of participants and the characteristics of the environment. Examples are drawn from three major studies involving over 11,000 students in public and alternative schools in Massachusetts. Results of the survey indicate that generally students viewed their schools as discriminatory, not challenging, and deficient academically. Students felt burdened by extra-school priorities and ambivalent about class attendance. Highly rated schools in the survey were those where teachers responded to students by observing their actions and seeking out their concerns. In comparing subgroup views, involved and marginal students, and students and teachers were examined. Members of both subgroups differ significantly in the way they perceive their school environment. Finally, the survey measured principal and teacher behaviors. Evidence suggests that principals who are considerate of teachers create school environments which students perceive as involved, humane, and friendly. A final section presents a method for planning which considers three dimensions of the curriculum: expressed, implied, and emergent (See SO 011 675). (KC)