Stock market game for kids: what it really teaches

Most stock market games for kids are trading contests: a virtual $100,000, about ten weeks, and a leaderboard ranked by portfolio value. That format teaches speculation, not investing. A better game teaches value investing — research a real company, say why you believe in it, and hold. Here's how to tell the two apart.

Most stock market games are trading contests

The best-known one is The Stock Market Game, run by the SIFMA Foundation since 1977 and played by nearly 20 million students. Teams of two to five students get a hypothetical $100,000 and about ten weeks. The scoring rule is public: winners are the teams with the highest portfolio value at the end.

Almost every alternative copies the format. HowTheMarketWorks gives students $100,000 in virtual cash with "real-time stock prices and rankings" — and lets teachers run anything from a semester contest down to a one-day trading challenge. Classroom platforms sell "live rankings" as a feature. Prizes go to the biggest ten-week gain.

Kids respond to the rules they're given. In a ten-week contest scored on ending value, a diversified portfolio almost never wins — a lucky, concentrated bet on something volatile does. Teachers who run the game say this out loud. "The way to win this competition is to break every rule of sound investing," Roger Shaffer, a teacher who ran the game for years, told The Wall Street Journal. In the same report, one student team borrowed $45,000 on margin to buy tiny biotech stocks. A student who played put it plainly: "In real life you probably should not invest this way."

The Journal's investing columnist Jason Zweig ended that piece with a warning for parents: if your kids are studying the stock market this way, "they might need to be deprogrammed."

To be fair, the games do teach facts. A randomized controlled trial across nearly 600 classrooms found that students who play score higher on math and financial-literacy tests. The problem isn't knowledge. It's the habit the scoreboard trains: trade fast, chase movers, win the quarter.

Why fast trading is the wrong habit

The habit has a measured cost in the real market. In the classic study of 66,465 households, Barber and Odean found that the most frequent traders earned 11.4% a year while infrequent traders earned 18.5%. The paper's title states its finding: "Trading is hazardous to your wealth." Morningstar's 2025 Mind the Gap study reached the same conclusion in six words: the more investors traded, the less they made.

Schools don't correct for this. In the OECD's PISA 2022 financial literacy assessment, most 15-year-olds had been taught about budgets (64%) and bank loans (63%) — but only 26% had covered compound interest, the one idea that makes long-term investing work. Kids learn transactions. Almost nobody teaches them time.

What is value investing?

Value investing is buying a piece of a real company because you believe the business will be worth more over time — then holding it while that plays out. The work happens before the purchase: understanding what the company makes, who pays for it, and what could go wrong. The skill it trains is judgment, not reaction speed.

It's the philosophy of Benjamin Graham and Warren Buffett, and it's built on patience. Buffett bought his first stock at 11 — three shares of Cities Service preferred, for $114.75. In his 2018 shareholder letter he calculated that the same $114.75, left in an S&P 500 index fund with dividends reinvested, would have grown to $606,811 over those 77 years. His description of his own approach, from the 1991 letter: the stock market is "a relocation center at which money is moved from the active to the patient."

A kid's version of value investing doesn't need spreadsheets. It needs four questions:

What does this company make?
Who buys it?
Why will more people buy it?
What could go wrong?

A 10-year-old can answer all four about Disney, Nintendo, Nike, or Roblox — often with sharper firsthand insight than an adult. That's Peter Lynch's "invest in what you know," and kids are natural at it. What they need is a game that rewards the four questions instead of the leaderboard.

A stock market game with no sell button

We built Kubrio's stock market project for kids around value investing instead of trading. Kids aged 9–13 invest paper money in real companies at real market prices — no cash, no card, no brokerage account anywhere in the product. The rules are what make it different:

There is no sell button. A pick is a decision to sit with, not a trade to flip. The habit being built is ownership, not timing.
Every investment gets a thesis, in the kid's own voice. Before paper money moves, your kid records a short spoken reason for the pick — the four questions. A thesis can be simple: "I pick Disney because I watch Disney every day, and my friends do too." Or bigger: "I think gaming companies will do well because everyone in my class plays games." Both are real theses. Both are the skill.
The AI pushes back — it never picks or grades. Tek, one of Kubrio's AI thinking partners, asks the harder question: who actually buys this? What would have to go wrong? It never names a company to buy, never writes the thesis, and never scores a pick right or wrong. The thinking stays your kid's.
Old theses come back. Months later the app resurfaces a recording so your kid can hear their own reasoning and check whether it held up. The portfolio becomes a journal of how they think, not a scoreboard.
There is no leaderboard by portfolio value. Nobody wins a week.

Paper capital grows with the thinking, not the returns. Kids start as a Shrimp with $10,000. Recording their first thesis unlocks Dolphin, with $100,000. The last tier is where you come in.

The $1 million portfolio your kid pitches to you

To unlock the Whale tier — $1,000,000 in paper money — your kid records a fuller thesis and formally sends it to you to co-sign. It's a review of their reasoning, not a payment step. You listen to the recording, ask your questions, and sign when you're convinced.

We designed this as a conversation, on purpose. Talking about how to pick a company — what it makes, who pays for it, what could sink it — is one of the best money conversations a family can have, and most families never have it. In T. Rowe Price's Parents, Kids & Money surveys, only 22% of parents discuss money with their kids at least weekly — yet an earlier wave found parents who do are nearly twice as likely to have kids who say they're smart about money (68% versus 36%). The PISA 2022 data points the same way: students who regularly discuss spending decisions with their parents score about 12 points higher in financial literacy.

The research on younger kids goes further. A University of Cambridge review for the UK Money Advice Service concluded that teaching young children explicit financial facts does little — what shapes their behavior is what adults model, chances to defer gratification, and making the future concrete. A thesis your kid defends to you, about a company they'll still own next year, is all three at once.

And yes, $1,000,000 is a deliberately big number. Your kid gets to practice thinking at portfolio scale — reading big numbers calmly, splitting a million across five companies, watching it move without flinching. Decades from now, a retirement account of that size is a number many of today's kids will actually have to manage. Better to meet it first when the money is paper.

How to start the conversation this week

You don't need the app to start — you need one company and the four questions.

Let your kid name a company they use. The maker of their game, their shoes, their snacks. Their pick, not yours.
Ask the four questions. What does it make? Who buys it? Why will more people buy it? What could go wrong? Resist answering for them.
Have them record the answer. A 30-second voice memo is enough. The point is saying the reason out loud, in their own words.
Set a date to listen back. Three months from now, replay it together and check the reasoning against what actually happened. That's the whole loop of value investing.

If you want the full version — real market data, the thesis journal, the tiers, and the co-sign moment — it runs as a Kubrio project: Pick 5 real companies for your $1M fund. It's one project from the games and simulators shelf: $39 on its own, or part of the Kubrio membership.

Frequently asked questions

What age should a kid start with a stock market game?

Ages 9–13 are the sweet spot for a research-based simulator like Kubrio's stock market project. Kids that age know real companies firsthand and can reason about who buys what. For younger kids, skip stock picking: the Cambridge research suggests what works before about age 8 is modeling patience and simple choices — saving for something, waiting for a bigger reward — not financial instruction.

Is The Stock Market Game free?

Not quite. The school program runs through state affiliates that typically charge $10–$30 per team, and it requires a teacher or class context. The official at-home version is offered as a thank-you gift for donations of $100 or more to the SIFMA Foundation. Kubrio's version runs at home with no classroom: one project for $39, or included in the membership.

Do stock market simulators use real stock prices?

Good ones do. Kubrio's stock market project uses real companies and real market data — the paper portfolio rises and falls with the actual market, which is where the learning is. Only the money is simulated: there's no cash, no card, and no brokerage account anywhere in the product.

Can my kid invest real money in stocks?

Minors can't open their own brokerage account, but a parent can open a custodial account and invest on a child's behalf. That's a real financial decision with tax and financial-aid implications — this article is education, not financial advice. A paper-money simulator is the no-stakes way to build the reasoning habit first.

How do I tell a good stock market game from a bad one?

Ask one question: does the game make my kid say why? If a pick needs a recorded or written reason — what the company makes, who buys it, what could go wrong — the game trains judgment. If the kid can tap buy and sell against a leaderboard, it trains trading. For a comparison of the options, see our guide to the best stock market games for kids.

Last updated August 31, 2026. This article is for education, not financial advice.

What does a stock market game really teach your kid?