This study was designed to investigate the similarities and differences among a group of four primary teachers in their approach to teaching. The four teachers worked together to interpret and teach a non-routine learning outcome for which no authoritative body of knowledge was readily available. This learning outcome was part of a comprehensive K- 12 curriculum that was being introduced to state schools throughout Victoria concurrently with changes in the managerial and administrative organisation of schools. The two major areas of study were the differences in teachers' orientation to teaching, based on their understanding of their role as teachers; and in their reaction to environmental factors, including teachers' reactions to changes in the curriculum organisation and the support they required to carry out these changes. The results in the study suggested that teachers' orientation to teaching was a major factor in the way they taught. It affected the way they interpreted the curriculum, the success of their professional collaboration with their colleagues and their teaching practice. Teachers differed in their orientation to teaching on a continuum that ranged from teaching for understanding to knowledge telling. The study illustrated the differences between teaching for understanding and an approach predominantly concerned with the transmission of a set body of knowledge. The equivocal nature of the knowledge associated with the learning outcome investigated in this study was unsuited to this latter approach to teaching. The broad, complex issues in the learning outcome were thus routinised to provide the stable, authoritative information that was more readily transmitted to students. The support required by the teachers differed. The more constructivist teachers obtained greater value from collaborative discourse, working together to form a shared professional interpretation of the learning outcome. The more constructivist teachers required extra time to plan and implement their work and this caused time pressures on their ability to cover the remainder of curriculum. The knowledge telling approach to teaching was less time- consuming. Students were able to be tested on the knowledge they had been taught. The evaluation of students' depth of understanding by the constructivist teachers was partly dependent on their judgement of individual students. This meant that they had less objective evidence that their teaching was worthwhile and that their students had benefited from it. Objective evidence of the completion of the learning outcome was important to the managerial structure in Victorian state schools as a form of accountability. The study raised questions about the compatibility of goals between management and curriculum in the Victorian Department Of Education (DOE). The different priorities of the different sections of the Victorian DOE were reflected in the different priorities of these teachers. It appeared likely that the constructivist approach to teaching would give way to more routine approaches if teachers failed to convince the community and other educationalists of the value of their approach.