Frequently curriculum implementation procedures consist of little more than teachers receiving descriptions of subject matter, definitions of new or technical terminology, and/or outlines detailing the surface steps of an instructional process. This case study analysis of how two high school teachers adapted some new curriculum features into their courses at the instigation and with the collaboration of the author suggests that efforts to promote this kind of sharing do not guarantee that teachers can or will adopt new curriculum. Those in a position to develop, implement, and evaluate curricula need to pay close attention to the circumstances through which innovations are introduced. They also need to maximize the opportunities for exchange between outsiders and practitioners as both attempt to develop and evaluate what curricular innovations mean in various classrooms. Rather than look at teachers as passive transmitters of information, and new curriculum as a thing ready to elicit a certain type of adoption behavior, curriculum planners and evaluators need to build instructional scaffolds that accommodate individual differences. It is important that training procedures and information take into account the in-place conceptual networks or meaning systems that filter teachers' evaluations of curriculum. Evaluators need to use procedures that will help them to begin to incorporate teachers' perspectives into their assessments of teachers' adoption behavior. (JD)