Background: Environments have a major influence on health and obesity risk behaviour. The primary to secondary school transition (PSST) within pre-early adolescence is a significant school shift associated with changing physical, academic and social environments. There is little evidence on the potential impact of a change in school environment on healthy weight behaviour.

Aim: To answer the following: How does a child’s nutrition and physical activity environment change over the primary to secondary school transition? What might implications be on eating and physical activity behaviour?

Method: A comparative case study design of primary, secondary and combined primary-secondary schools following Victorian school children across the PSST. Schools will be selected from areas of similar SEIFA index within Victoria, Australia. School environment (food/physical activity) audit data and school readiness capacity for addressing childhood obesity will be collected by questionnaire from staff within each school. Environmental audit data analysis includes existence/awareness of policy, available resources and teacher perspective of healthy environments. Readiness capacity data will be analysed to give an average score of readiness stage per school. Descriptive statistics and Wilcoxon paired rank test analyses will be conducted between each pair of primary and corresponding secondary school.

Significance: Understanding primary and secondary school healthy/obesogenic environments is critical for providing context of any eating or physical activity behavioural change as children transition from primary to secondary school, and for informing future intervention to promote healthy behaviour.