Our system administrator standardized on our using as userid the part of students' e-mail address that precedes the @ sign. That way they're not so long. This works because each student has an "official" university e-mail address of the form xxxx@student.umass.edu, so the xxxx part is unique.
It's easy enough to strip that part off from the whole e-mail address either in a spreadsheet or else by using some script.
WeBWorK Main Forum
Handing Out Passwords
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