Purpose: The article offers a progressive reading of ESD with a teaching example to decolonise SSE despite constraints set by the school system. Design/methodology/approach: The article presents ESD's idea of thought within 'the big picture' of global education. After that, a description of an expert group is given, tasked with developing a conceptual framework for SSE, commissioned by the school administration in Germany and critically reflected on amidst system constraints. Findings: Full-fledged reforms to rethink schools in the 21st century from scratch to efficiently decolonise and integrate ESD are required. Research limitations/implications: The last part of the article is limited in its description and critical reflection of the federal German example. Practical implications: It is recommended that the big picture in terms of promoting global and decolonial dimensions of ESD and facilitating a sustainable transition of schools for achieving the SDGs is kept in sight.