This paper reports research aimed at understanding how teachers use innovations and suggests that the intentions of teachers, explored through forms of self-report, are an important clue. Eight teachers in three English comprehensive schools participated in a study of their use of the United Kingdom Schools Council Integrated Science Project (SCISP). This project was chosen for study because it asked teachers to take seriously the discussion of value issues in science in the context of integrated subject matter, with an aim of changing student attitudes and evaluating these changes. Interviews, participant observation, and questionnaires were employed to study the use of the project. The teachers also participated in two one-hour clinical interviews in which constructs about their teaching methods were elicited. Analysis of the constructs suggests that teachers construe their practice in such a way as to reduce ambiguities associated with their work. The paper shows how these teachers adapted the innovative materials so as to minimize sources of role diffuseness inherent in the doctrine of the project. The results suggest that the teachers operated functional systems designed to permit stable classroom relationships. (Author/MLF)