Preparing school teachers goes beyond equipping them with instrumental knowledge of curriculum, pedagogy, and experiences of how this can be enacted in practice. They must be prepared to understand and encompass compelling social issues of justice, equity, and sustainability. To do this they need to understand pressing environmental issues as a forerunner to incorporate sustainability into their teaching. This paper uses survey data from a sample of 136 Australian pre-service teachers to gauge their knowledge and beliefs about sustainability, as well as their level of concern and their inclination to teach about it. The results show sound levels of knowledge of the biophysical environment, knowledge about the consequences of unsustainable practices and the effects of energy use and its contribution as one cause of climate change. Some also hold misconceptions about the causes of climate change. Most prospective teachers are ready to take action to protect earth systems through personal actions, and teaching and advocating within their school community, and less likely to undertake political activities beyond the school. Results from this sample are used to set out a challenge to use the concept of powerful knowledge in tandem with everyday knowledge to improve sustainability instruction in teachers’ preparation programs to capitalise on their potential to contribute to Education for Sustainable Development.