At present, Special:Students shows almost every student as having today's date for both "first enrollment" and "last active".
What is supposed to define "active" for a student? Edits and/or log actions?
It also includes users who aren't enrolled in any courses. (These appear to be people who enrolled in a course to test the enrollment interface, and then unenrolled.) As the number of students increases, and the first wave of classes ends, this page will need filters for viewing students by term, or all students in active classes, or all students in past classes.