This paper describes summative evaluation of the Quest project conducted at four case-study schools. The schools were selected for their high involvement in Quest, varied interpretations and uses of the project, and diverse locations and demographic constitutions. Data collection included participant observation, individual and semistructured group interviews, pre- and post-test score analysis on the "School Professional Staff as Learning Community" survey test, Reflective Assessment questionnaires for school staff, and state-mandated student achievement test scores. Results varied unevenly across the study sites. For example, one well-funded school serving mostly middle-class students showed little improvement in student achievement and professional learning community, whereas two schools serving less advantaged students improved dramatically in professional development with ambiguous outcomes in student performance. Interviewees, however, consistently described their participation in Quest as personally and professionally meaningful. Findings revealed tensions between the schools' needs for flexibility in implementing reforms and external demands for standardized achievement scores. Another tension involved the relatively more evident influence of the Quest project at the individual level versus a more ambiguous influence at the level of school district or state department of education. The appendix includes a Quest brochure and a framework for continuous improvement. (Contains 52 references and 7 tables.) (RT)