This doctoral research explored the impact of whole-school education for sustainability on upper-primary students and their families. More specifically, it examined: organisational factors that foster or impede the establishment of school sustainability programs; the environmental knowledge, attitudes and behaviours of upper-primary school students; the family dynamics that influence intergenerational transfer of pro-environmental behaviours between students and their families; and identified factors that potentially maximised the impact of whole-school education for sustainability. A multiple comparative case study approach was utilised, involving three primary schools with populations of similar socio-economic status in Perth, Western Australia. Two of these schools were connected with the Australian Sustainable Schools Initiative – Western Australia (AuSSI – WA) and the third was not involved with any sustainability or environmental education providers. The case study design included mixed methods of data collection, triangulated for analysis. Methods included surveys, mind maps, interviews, observations and document searches. Results indicated that effective whole-school sustainability education requires: visionary, committed school leadership; collaborative governance that invites participation from all staff; a few core staff to spearhead projects; contextualised professional learning opportunities; and authentic engagement of student voice. When these elements are prioritised, school sustainability programs can have a positive impact on students’ knowledge about ways they can care for the environment and attitudes towards school environmental activities. Furthermore, when sustainability facilitators work closely with schools these outcomes can be maximised.