Do public education platforms increase online course participation? Evidence from a difference-in-differences study of German adult education centres

Following the sharp increase in online courses during the COVID-19 pandemic, online education platforms have gained growing relevance. While research has investigated effects of platforms on learning outcomes, this study is the first to empirically evaluate adult education platforms with respect to online course participation. Three of Germany’s sixteen federal state associations of public ‘adult education centres’ (Volkshochschulen, VHS) have implemented online platforms called ‘onlinevhs’. We use this case to employ a heterogeneous difference-in-differences estimator, accounting for staggered implementation across federal states and time. The results indicate that the platforms themselves have no causal effect on online course participation. Although a model without covariates suggests a positive effect, this is explained by pre-existing regional and organisational differences between VHS with and without platform adoption. Overall, the platforms reproduce existing disparities in online participation rather than reducing them. The results indicate that the implementation of a platform alone is insufficient to increase online course participation. Therefore, careful consideration should be given to how a platform is designed and what additional measures are required. Additionally, the study contributes to the theoretical discourse on the efficiency of public platforms, as it shows that an imitation of commercial platforms might not lead to the desired results.