In this study, three interactive, online modules on Universal Design for Learning (UDL) were delivered over four weeks with teacher candidates to improve their skills and knowledge for developing and implementing lesson plans based on UDL principles. Eight teacher candidates who were in a dual certification degree programme (i.e. general and special education) and enrolled in a graduate-level course participated in the study. After completion of the modules, the candidates significantly enhanced their ability to design lesson plans based on UDL principles and reliably implement the lessons during their student teaching placements in both high- and low- technology settings. The candidates described the discussion forums shared with their peers as the most useful aspect of the modules for promoting their learning. Additionally, teachers revealed a strong willingness to apply the principles of UDL in their future teaching. Limitations and implications are discussed.