Click on the "Unique ID" link
You must be a course master or instructor with roster-editing privileges to see students' Unique IDs as links.
Changing a student's Unique ID will need to follow the parameters defined in the Student Id filter field in the Global Course Settings page of the Course Wizard. If an improper id is entered, then a browser alert will appear informing you of the error and what the parameters are.
A student can also change his or her unique ID from the course accounts page.
Note: Editing the Unique IDs of students could result in the automatic change of their payment status (found in the Status column).