Have them predict their mark before you hand it back

Classroom studies of grade prediction show a consistent pattern: predictions are overconfident, and the lowest performers are the most overconfident, while high performers often undershoot (Hacker, Bol, Horgan & Rakow, 2000). That miscalibration is invisible to the student until you surface it, and surfacing it costs thirty seconds before you return the stack.

In practice

• Before returning marked work: "Write the mark you think you got, and the question you're least sure survived."
• The debrief question isn't "what did you get?" but "which way were you off, and where?" Repeated over a term, predictions tighten, and that is self-assessment being learned.
• Watch for the student who is always 20% high: they don't need more content, they need to see the rubric applied to their own work (see "Ask how sure they are").