This paper focuses on the emergency remote teaching during the temporary shutdown of physical learning environments in the spring of 2020. It presents findings from a survey among about 14,000 Danish teachers and students at vocational colleges and upper secondary schools regarding their experiences with online education. The analysis and interpretations of the survey data provide evidence suggesting that the teachers generally need professional development regarding online education and blended learning events. Most often, they did not succeed in their attempts to realise the potentials of online education: First, they did not manage to coordinate their expectations regarding the students’ daily workload and meet their individual need for teacher support. Second, they did not provide clear announcements and formative feedback. Third, they had difficulty supporting students experiencing learning difficulties and they did not support students with motivational challenges due to social isolation.To overcome these challenges, teachers need to be more informed by data and research than they were during the emergency remote teaching. This includes information derived from analysis of local data on students’ independent and collaborative work, learning challenges, and perceived self-efficacy. Moreover, it includes information about the main findings in research about the benefits of blended learning compared to online teaching and f2f teaching.