Do I have to hand over the recordings I made as a student as part of my studies to the education institution?
No, there is no need to hand them over unless this is (temporarily) necessary for assessment. You also retain the copyrights in your self-made recordings, unless you assign these rights to the institution in a signed declaration.
However, the institution can negotiate some user rights with you. One such rights may be that the resources included in your digital portfolio remain available electronically for a certain period of time, for example for use as study resources by other students or lecturers. If the institution has made the recordings possible in whole or in part (with funding or by making facilities available), it is reasonable that it may also impose certain requirements with regard to the exploitation of the recordings. The course's organisers can arrange this in accordance with the general terms and conditions associated with your enrolment as a student.
If the recordings are of particular interest and offer unexpected exploitation opportunities, it offers the student and institution more certainty if you conclude a separate licence contract. If a lecturer wants to use your recordings to explain a certain subject matter in education, your permission is required, unless the recordings have already been shown in public with your permission. In that case, they have already been disclosed and the lecturer can use them in an educational setting based on the exceptions for education. Based on these exceptions, you can ask for fair compensation. You can also agree on EUR 0 in compensation.