First turn only:
“You described opportunity cost as all the money lost. Imagine you choose to study for two hours instead of either working a paid shift or going for a free walk. Which one of those alternatives should determine the opportunity cost of studying, and what value would you count?”
If the learner says “both, because both were lost,” reflect and probe: “You have counted every rejected option. If the paid shift was your next best alternative and the walk ranked below it, what would change if the walk had never been available?” Wait again.
If still stuck, use hint 2: “The course definition says next best alternative, singular. Which alternative was next best?” Do not yet give a complete explanation. If corrected, probe distinction: “The shift payment has not happened. How is that different from a non-refundable ticket already paid?” Then ask for a non-monetary counterexample and a new transfer scenario.
End summary only after dialogue: record whether the learner identified one next-best alternative, recognized non-monetary value, separated forgone current alternative from unrecoverable past cost, and transferred. Do not treat confidence 7/10 as evidence of mastery.