One of the effects of the 1989 Education Act in New Zealand was to allow schools to broaden their client base. This had the most significant impact in the area of schooling where there was the greatest possibility for change, particularly for the classes either side of the transition between primary and secondary schooling; the middle years. Under the Act, primary schools had the option of recapitating to retain their older pupils. Secondary schools were now able to extend downwards and offer a junior high school structure. So, the greatest potential for school restructuring was associated with the intermediate schools. Traditionally, intermediate schools had provided a two-year transition at Years 7 and 8 between primary and secondary education. The 1989 Education Act allowed them to extend this to include Years 9 and 10 and the development of three or four-year middle schools. In their traditional role of providing a transitional stage between primary and secondary education, the intermediate schools were characterised by aspects of both institutions. While programmes were largely home-room based and under the care of one teacher, some subject specialisation was also characteristic of intermediate schools. That this structure could be extended into the lower secondary classes offered a new perspective on the role of middle schooling. It was the extension of a Year 7 and 8 intermediate school into a four-year middle school and thereby encroaching on the traditional preserve of secondary schools, that became the focus of this study. It monitored the expansion of a two-year school as Years 9 and 10 classes were added and the transition of the first Year 10 class into Year 11 at secondary schools. From this focus, the study hypothesised three main concerns relating to change: that the development of a two-year institution into a four year one would offer significant challenges to both the school organisation and the delivery of the curriculum, whether the students who chose to stay at the Middle School viewed the experience as worthwhile and that a current theory on institutional change would be useful in observing and analysing the data. The methodology for the study was largely qualitative. It was based on interviews with the Years 9 and 10 pupils, their teachers and parents and the school principal. The interviews covered the time in which the Middle School expanded to accommodate the additional two years, 1995 and 1996, and also followed the pupils into the first term of their secondary schools in 1997. During the transition to secondary schools, the interview data was supported with observations and pre-transition and post-transition surveys, using Q-Sorts and Picture Interpretation methods. In addition, parents’ views were sought on their children’s experiences at the Middle School and their transition to secondary schools. The research confirmed that a Year 7 to 10 school offered a viable alternative for the pupils in this study to the traditional path of transition from intermediate school to secondary school at the end of Year 8. It suggested that a school organisation, based on home-room teaching and interdisciplinary staffing arrangements, provided a useful basis for the social and educational development of preadolescents, although quite what would comprise a suitable balance between generalist and specialist teaching proved challenging. Nevertheless, curriculum delivery for Years 7 to 10 was facilitated by a flexible form of organisation. Parents of the Year 9 and 10 pupils endorsed the practices of the Middle School and confirmed that delaying transition to secondary schools was worthwhile. The development of the Middle School from a two-year to a four-year institution was viewed from a Perspectives theory of change. The theory was found to present a useful focus for viewing school change, but some modifications to it are offered.