If practice makes perfect, then practice should be compulsory?!

With the conversion to Bachelor's and Master's degree programmes, workload became important for accreditation and the development of student competences. Exercises, which are increasingly offered online, are an essential element of university teaching. The question that arises is whether these exercises should be offered on a mandatory or voluntary basis. Within two lectures, exercises were offered over three years in an experimental setting on a voluntary or obligatory basis. This paper discusses both the student workload for the content offered (i.e., time on task approach) and the output of the respective settings. N = 1,329 students took part in the study, and the results show that compulsory exercises lead to deeper discussion and better results.