There is a paucity of research in Australia on the nature of young people's attitudes, knowledge and actions. This paper reports on the findings from one such study of Australian high school students. The research was based on a survey of 5,688 students form Melbourne and Brisbane. These young people identified protection of the environment as the most important problem in Australia and strongly supported the belief systems characteristic of an "environmental paradigm". Despite this, the majority displayed relatively low levels of knowledge of key environmental concepts, and were involved in little environmental action-taking outside of household activities. Differences are reported between: students from Melbourne and Brisbane: girls and boys; high performing and general schools; and teacher and students. The paper concludes with a discussion of some implications for environmental education in Australia.