"You be the examiner!" is an online approach to providing students with immediate, readily accessible, and nonthreatening feedback on their understanding of key biochemical concepts. The feedback aims to affirm correct understanding and, where further study appears necessary, direct the student to the relevant sections of their textbook and/or lecturer-provided study notes. Rather than providing model answers to previous examination questions, "You be the examiner" asks the students to evaluate typical "student" answers to such questions. Instead of a single "correct" answer, students encounter a range of answers that they must assess for accuracy and appropriateness. (Contains 1 figure, 1 table, and 2 appendices.)