This is similar to oral math exams in Danish high school. The main differences being that the teacher submits the curriculum, and the student draws 1 topic on

This is similar to oral math exams in Danish high school. The main differences being that the teacher submits the curriculum, and the student draws 1 topic on the day of the exam and is given something like 20 minutes to prepare between drawing and presentation. All submitted topics are known to the student, through the submitted curriculum, which has all been taught throughout the year(s). Grade is dependent on how well you do the proof related to the topic and how well you manage to reference related topics in the curriculum.