We discuss the repercussions of the intensification and heterogeneity of contemporary migrations, especially forced migrations, in compulsory schooling contexts in Portugal. Our objectives are (i) to identify the major educational challenges arising from transnational migration, (ii) to understand how schools, still very much rooted in an educational-pedagogical nationalism, adjust to these challenges and (iii) to understand the practices of educational agents in complex circumstances and subjected to many constraints. We draw on data from qualitative fieldwork that we have been carrying out for seven years on the settlement and integration of migrants in the North and Centre of Portugal. From the analysis of this data, we found that schools have been gradually adapting to the multiple challenges (support, resources, skills and specialised pedagogies) raised by migration. The discretionary capacity, informality, creativity and goodwill of educational agents have been fundamental to this, often compensating for the lack of guidelines and resources.