As I passed them the money I told my story. Shortly after coming to Mongolia I made friends with a police officer who was involved in busting a ring of counterfeiters. My police officer friend gave me one of the counterfeit bills as a gift.
The students diligently handled the money, looking at both sides trying to spot differences in the design work, ink, layout, etc. They held it up to the light. They rubbed the paper to see if the texture was the same on both bills. They even opened their wallets to compare the bills with their own. They questioned each other about their opinions. After a few minutes of back and forth I took the bills, held them up for everyone to see and ask the students to vote. Which bill was real? Which bill was fake?
All of the students gave their answer, choosing one bill or the other as real or fake. I held the bills high, pausing for dramatic effect, watching as the students sat, some on the edge of their seats, waiting to find out which bill was counterfeit. I made my announcement.
They were both real. My story was a lie.