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Level 2 · ages 9–12OECD RRSpend

Opportunity cost

🎯 Goal: Understand that choosing to use money/time for one thing means giving up another — the "missed option" is the opportunity cost.
Money and time are limited. Choosing A means you give up B. What you forgo is the opportunity cost.

Let’s explore

🔀
Every choice has something forgone — that is the opportunity cost.
💡
Buying a 50k game means missing a 50k book with the same money.
🧠
Thinking about opportunity cost helps you pick what is more worth it.

Practice activity

⚖️ With 50,000d choose a game OR a book. What is the opportunity cost of choosing the game?
Worked example: You have 50,000d and choose the game. The opportunity cost is the 50,000d book you did not buy. You weigh: which is more worth it to you?

Quick quiz

1. Opportunity cost is?
→ What you give up to choose another
2. Buy a 50k game instead of a 50k book, opportunity cost is?
→ The 50k book
3. Why does every choice have an opportunity cost?
→ Money/time is limited
4. Thinking about opportunity cost helps you?
→ Pick what is more worth it
5. Spending all evening gaming instead of studying, opportunity cost is?
→ The lost study time

🎯 Real-life mission

When you choose A over B, write down what you “gave up”.
Open the interactive app →

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Rùa Vàng — Financial education for Vietnamese children · Aligned with OECD/INFE
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