This paper, presented in three parts, overviews the current understandings of the Earth System and the relatively recent interdisciplinary field of Earth System Science (ESS) from a school education perspective. The representation of ESS in the Australian Curriculum is explored through the Cross Curriculum Priority area of Sustainability and the Australian Curriculum: Science (F-12), although the focus is up to Year 10. Initially the most current ESS framework and concepts (Steffen et al. 2020) are introduced (Part I). In the first of two follow-up journal articles an analysis of the Sustainability Cross Curriculum Priority area and the Australian Curriculum: Science indicated that several key ESS understandings and system-thinking skills were present. How the most current ESS understandings and abilities could lead to a far deeper understanding of the Earth System are then considered and those that may need more attention from students and teachers are highlighted (Part II). The final article outlines several research-informed pedagogies to help learners develop more scientific understandings of the Earth System, and appropriate related abilities (Part III). These Earth System goals and pedagogies needed to be considered in the ACARA review of the Australian Curriculum: Science and the Sustainability Cross Curriculum Priority area -- to that end, this paper was submitted to the appropriate committees. We believe the suggested ESS additions and emphases could comprise one pathway toward a more comprehensive and confident Earth System literacy and a stronger engagement in the Earth and other sciences at every school level, and to the curriculum as a whole. Better-informed, sustainability decision-making and actions by students as today's, and tomorrow's, citizens is the hoped-for outcome.