This article is based on qualitative and quantitative data collected from teachers and pupils in Danish schools in June 2020, as schools reopened following closures in the spring due to the COVID-19 pandemic. It investigates the transformations in school life that took place in this period in response to strict official guidelines to prevent the spread of infection, transformations both in school learning environments and in teaching activities. Using factor and cluster analyses and logistic regression, it explores the relation between teaching environment and pupils' emotional, social, and academic wellbeing, identifying correlations between key factors in the environment and the three dimensions of wellbeing. The study contributes both to understanding and dealing with the crisis in which education systems in the Nordic countries have found themselves in and adds relevant knowledge on themes of importance for education in the future.