Computer-assisted assessment (CAA) is widely used in modern university courses in many different fields. It can be used both in formative and summative assessments and with different emphasis on (self-)training, grading, and feedback generation. This article reports on experiences from using the CAA tool "JACK" to support a university lecture on mathematical statistics for exercises, tests, and exams. We show and discuss, among others, a positive relationship between usage intensity of JACK and final grades. Moreover, students generally report to invest more time into studying when offered a CAA, and to be satisfied with such a setup.