Exam stems under fatigue: what error logs teach quietly

High‑stakes exams punish speed reading. We asked participants to log the exact line where their reading diverged from the stem writer's intent, even when the answer still landed correct. Those logs revealed pronoun attachment errors clustered near midnight study sessions.

A second pattern involved over‑weighted acronyms. When stems introduced a new acronym late, tired readers imported definitions from earlier questions. A simple highlight rule—circle acronyms introduced after sentence three—cut that error class dramatically.

We end with humility: logs help but cannot replace sleep. Facilitators now publish a hard stop time instead of optional night problems. Scores did not drop; retention of nuanced rationale improved.