The aim of this study was to develop a theoretical understanding of the process and strategies school organization members engage in when faced with issues concerning schoolwide curriculum change initiatives using a grounded theory approach. Building on this new theoretical understanding, the study aimed to explore factors and conditions that are needed to implement effective and meaningful interdisciplinary teaching and learning environments in the whole school. Most of the relevant data came from field notes of classroom observations, and several meetings that were held regularly over a two year period, with a study group that comprised of teacher education professionals, school administrators, and teachers in the primary and secondary divisions from a K-16 school in Japan. The study suggests that, ‘Vaguing’, (which emerged as a core category in this grounded theory study), a behaviour that organizational members including leaders exemplify when an organizational change initiative is suggested, plays a key role in contributing to the ongoing struggle in the design and implementation of successful schoolwide curriculum reform initiatives.