If you really want to get their attention (only works for actual students) pile their transcripts in front of the building and give them 10 minutes to leave the building before you burn them.
As a friend once said, “I like the cut of your jib.” Hilarious idea.
That could be a new game show. See how fast they go from sitting to the door starting when the flame gets lit.
On the other hand, those that are sitting there are likely “Studies” students. Their degrees are pretty much worthless anyway. STEM students are usually too busy with learning useful skills.