CMU did (maybe still does?) have a mandatory, once-a-week course to orient new students to logging in to *nix workstations, setting file permissions and copying files around on AFS, etc. Whether this was just for CIT or university-wide I cannot recall.

Didn't they recently nuke the unix infrastructure and replace it with cloud services? Or have reports been exaggerated?

The unix infrastructure is still in place and widely used by nearly all cs courses.