The quickest way into quantum computing with a class: the browser games. They run on any phone, tablet or laptop with a web browser — nothing to install, no accounts, no cookies, no personal data, only anonymous visit counts (see privacy). Thirty students can play at once. The Jupyter notebooks behind the games are for older students who want to see the Qiskit code.
Printable handout ▸
Lesson plan
No prior knowledge needed. Students play in pairs (coin game, CHSH) or in teams of three (GHZ).
| Time | What happens |
|---|
| 0–5 min | Hook. On the projector: "Can you beat a computer at flipping a coin?" Play one round of the Quantum Coin Game, chapter 1, with the class. |
| 5–15 min | Superposition. In pairs: Quantum Coin Game, chapters 1–3. Against the quantum computer everyone loses, every time, as long as the computer starts — chapter 3, "Look inside the box", shows why: the H gate puts the coin into superposition, and a second H brings it back to heads. |
| 15–35 min | Entanglement. The GHZ Game in teams of three, or The CHSH Game in teams of two. First the classical team: no strategy wins every round. Then the quantum team, sharing entangled qubits, does better than any classical team. |
| 35–45 min | Debrief with the questions below. |
Questions for the debrief
- The quantum computer won every round of the coin game. Was it cheating? What move does it have that you don't?
- Did the quantum team talk to each other after the questions were asked? How can they do better than any team that only agreed on answers beforehand?
- Real quantum computers make errors. What do you think happens to the quantum team's score on one? (Older students: GHZ on Real Quantum Devices.)
The games at a glance
3 games play right in the browser; all of them come as a Jupyter notebook with the Qiskit code, which opens in a free online session (first start can take a few minutes). Times and goals are for the notebooks.
Superposition & interference · ~20 min · level: beginner · ▶ plays in the browser
Prerequisites: None
In the notebook you:
- Describe superposition: a coin that is heads and tails at once until you look
- Explain why two Hadamard moves bring the coin back to heads (interference), so the quantum player wins every round
- Read a one-qubit circuit with H and X gates
Entanglement (GHZ states) · ~40 min · level: beginner · ▶ plays in the browser
Prerequisites: None; the last part uses vectors and matrices
In the notebook you:
- Show that no pre-agreed answers win all four questions of the GHZ game
- Use a three-qubit GHZ state and color (X) and shape (Y) measurements to win every round
- Build the measurement circuits in Qiskit
Bell test, entanglement · ~25 min · level: intermediate · ▶ plays in the browser
Prerequisites: Superposition (the Quantum Coin Game)
In the notebook you:
- Work out why no classical team wins more than 75% of the rounds
- See how an entangled pair, measured at the right angles, wins 85.4%
- Connect the game to the Bell tests behind the 2022 Nobel Prize in Physics
Quantum contextuality · ~25 min · level: intermediate
Prerequisites: Entanglement (the GHZ or CHSH Game) helps
In the notebook you:
- Prove that no 3×3 square of 0s and 1s meets all six parity rules, so a classical team wins at most 8 of 9 questions
- See how two shared Bell pairs and a square of Pauli measurements win every round
- Explain why the proof fails for quantum measurements: they don't commute, so the nine results never exist all at once (the Kochen–Specker theorem)
Nonlocality without inequalities · ~20 min · level: intermediate
Prerequisites: Entanglement (the GHZ or CHSH Game) helps
In the notebook you:
- Follow how three facts that always hold rule out one outcome for any classical explanation
- See both cars come out diesel anyway in 1 of 12 mornings when both inspectors check the engine — up to 9.02% with the best measurement angle
- Recognize nonlocality without an inequality
Quantum game theory · ~20 min · level: intermediate
Prerequisites: None; game theory basics help
In the notebook you:
- Explain the classical prisoner's dilemma and why both players defect
- See how entanglement makes cooperation pay when the players may only use a restricted set of moves
- Find the catch: with every one-qubit move allowed, every move has a counter — only random strategies are stable, for example both choosing completely at random, worth 2.25 points each (between 1 and 3)
Grover's search algorithm · ~15 min · level: intermediate
Prerequisites: Boolean logic (AND, OR, NOT); some Python
In the notebook you:
- Write a logic puzzle as a Boolean formula and let Qiskit turn it into a quantum oracle
- Run Grover's search: an oracle marks the answers, a diffuser amplifies them by interference
- See it find the answers in about √(N/M) rounds instead of about N/M checks (N candidates, M answers)
Error mitigation, transpiler optimization · ~25 min · level: advanced
Prerequisites: The GHZ Game; Python and Qiskit
In the notebook you:
- See how noise on simulated IBM quantum computers costs the quantum team rounds
- Choose good qubits, by hand and with the transpiler
- Correct readout errors with readout error mitigation, and know its limits
The day before
- Open the games on the devices and the school network your class will use.
- On the projector, zoom the browser (Ctrl + or ⌘ +) until the back row can read it.
- Notebooks: start each one you plan to use once beforehand. For a whole class, prefer the browser games — thirty notebooks starting at the same moment can be slow.
- Print the handout, one per pair.
Need help?
Planning a workshop, a project day or a booth? We help you prepare it, free — workshops & events. Found a mistake or have an idea for a game? Open an issue on GitHub.
