Over three years, dialogue groups from the Global South and North collaborated in a transnational »Global Campus Online,« a laboratory uniting scientists with activists from arts, culture, and civil society. Together, they developed practical, small-scale projects addressing the 17 Sustainable Development Goals. This volume presents initiatives with disadvantaged communities, including Roma in Hungary, marginalized women in South Africa, and Guaraní in South America. The contributions promote climate justice, inclusive cities, and empowering education for all ages. A concise exploration of Global Citizenship Education from the grassroots, highlighting how local action and global exchange can drive sustainable change.