This paper describes the design and delivery of a postgraduate course on “Design and Evaluation of Interactive Systems”, part of an M.Sc. program on Human-Computer Interaction jointly offered by the Computer Engineering and Informatics Department and the Department of Electrical and Computer Engineering. This course was initially intended to use the flipped classroom model but was shifted online due to the COVID-19 lockdown imposed during the Spring 2020 semester. The paper discusses student attitudes towards the online flipped classroom model and draws preliminary conclusions on the advantages and limitations of the approach. Qualitative and quantitative assessment data indicate a positive overall students' perception of the online flipped classroom model.