(1) Use candy bars, not gift certificates. (2) Don't tell about the gains from trade before you do the game, for goodness sake. Have them do the game and then draw the moral of gains from trade from what they have experienced.
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(1) Use candy bars, not gift certificates. (2) Don't tell about the gains from trade before you do the game, for goodness sake. Have them do the game and then draw the moral of gains from trade from what they have experienced.