Across Australia many young people are taking action to address the issue of climate change and educating others through leading grassroots activism on local and global issues of sustainability. This paper discusses findings from an online document analysis that investigated three case studies of how youth-led organisations in Australia are leading and developing human rights-based education for sustainability (EfS) to empower others to enjoy and exercise their rights in keeping with the guidance of the 2011 UN Declaration on Human Rights Education and Training. This paper discusses how these organisations represent their activism online to empower young people to lead democratic action to achieve climate crisis justice. Drawing on a conceptual framework developed by Jensen & Schnack, the authors argue that the data suggests that the young activists in these case studies demonstrate high levels of 'social action competence' through raising awareness and taking action.