EconSim
Game theoryClassroom · multi-user

Trust Game — Trust & Reciprocity

Paired up, a Trustor sends some of 100 points, it triples on the way, and the Trustee chooses how much to send back. See how trust creates value and reciprocity sustains it.

You’ll learn: See why people send and reciprocate even when self-interest predicts sending nothing — and how trust unlocks a surplus that benefits both sides.

Teacher guide

Students will learn to

  • Experience both sides of a trust exchange: deciding how much to risk, and how much to repay.
  • Contrast the game-theory prediction (send nothing, return nothing) with what real people do.
  • Connect the multiplier to the surplus that trust creates, and returns to reciprocity and reputation.

Before the session — ask

  • If sending money to a stranger tripled it, but they decided how much to send back, how much would you send?
  • What would a purely self-interested Trustee return — and knowing that, what should a self-interested Trustor send?

After the session — discuss

  • How much did Trustors send on average, and how much did Trustees give back?
  • Did pairs that trusted more end up better or worse off than the 'send nothing' prediction?
  • Where in real life — lending, charity, business deals — does this same trust-and-repay dynamic show up?

Timing

  • Briefing & pairing3–5 min
  • Send & return4–6 min
  • Reveal & discussion8–10 min

Run it with your class

Students join with a code or QR — no account needed. Teachers start a session from the dashboard.

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