> Nowadays, there are quite a lot of classes that you have to sit in (depends a lot on the university and courses)
Higher education institutions are bound by the "freedom of study" ("Freiheit des Studiums") derived from the provisions on academic freedom in the German constitution (Art. 5 Grundgesetz) and explicitly formulated in the Framework Act for Higher Education (ยง 4 Hochschulrahmengesetz). Also it is not directly mentioned, the legal interpretative tradition of these provisions tends to be that the freedom of study implies that compulsory attendance is only permissible if a certain study content cannot be acquired autonomously (e.g. for laboratory courses or seminar discussions). As this is not usually the case for simple lectures, compulsory attendance may not be required for them. I myself was involved in drafting study regulations in the late 2000s in which this had to be specifically taken into account. I am aware that not everywhere such attention is given to this and that there exist different opinions about the exact limits of the freedom of study. However, study regulations that include extensive attendance requirements run the risk of not standing up to legal scrutiny.
Higher education institutions are bound by the "freedom of study" ("Freiheit des Studiums") derived from the provisions on academic freedom in the German constitution (Art. 5 Grundgesetz) and explicitly formulated in the Framework Act for Higher Education (ยง 4 Hochschulrahmengesetz). Also it is not directly mentioned, the legal interpretative tradition of these provisions tends to be that the freedom of study implies that compulsory attendance is only permissible if a certain study content cannot be acquired autonomously (e.g. for laboratory courses or seminar discussions). As this is not usually the case for simple lectures, compulsory attendance may not be required for them. I myself was involved in drafting study regulations in the late 2000s in which this had to be specifically taken into account. I am aware that not everywhere such attention is given to this and that there exist different opinions about the exact limits of the freedom of study. However, study regulations that include extensive attendance requirements run the risk of not standing up to legal scrutiny.