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Quantum Wonders

Eighteen free cards about the strangest true physics we know. Each card holds one quantum idea: a picture to remember it by and one sentence a ten-year-old can follow. Open a card for what’s really going on, a common myth, and where to read more.

For ages 10 to adult · 18 free cards · Free to share and print

See the cardsTwo games to play

Tiny Worlds

How small atoms are, and what’s really inside them.

Quantum Wonders card QTM-02, Mostly Empty Space, with a glowing paper-cut illustration. It reads: If an atom were as big as a stadium, its nucleus would be about the size of a pea in the middle. Mostly Empty SpaceQTM-02Quantum Wonders card QTM-03, Energy Comes in Steps, with a glowing paper-cut illustration. It reads: Light’s energy comes in tiny packets called quanta — more like a staircase than a ramp. Energy Comes in StepsQTM-03Quantum Wonders card QTM-05, Electron Clouds, with a glowing paper-cut illustration. It reads: Electrons don’t circle the nucleus like planets. They spread out in clouds that show where they are likely to be found. Electron CloudsQTM-05

Waves & Particles

Light and matter that travel like waves and arrive like dots.

Quantum Wonders card QTM-10, Wave–Particle Duality, with a glowing paper-cut illustration. It reads: Light and electrons travel like waves but arrive like particles, one dot at a time. Wave–Particle DualityQTM-10Quantum Wonders card QTM-11, The Double-Slit Experiment, with a glowing paper-cut illustration. It reads: Send electrons one at a time toward two slits, and a striped pattern still builds up — as if each went through both. The Double-Slit ExperimentQTM-11Quantum Wonders card QTM-16, Quantum Tunnelling, with a glowing paper-cut illustration. It reads: A particle can sometimes turn up on the far side of a barrier it doesn’t have the energy to climb. Quantum TunnellingQTM-16

Chance & Measurement

Odds, blends of possibilities, and what happens when we look.

Quantum Wonders card QTM-19, Superposition, with a glowing paper-cut illustration. It reads: Before it is measured, a quantum particle can be in a blend of possibilities — not just one we haven’t checked yet. SuperpositionQTM-19Quantum Wonders card QTM-22, The Uncertainty Principle, with a glowing paper-cut illustration. It reads: A particle can’t have both a perfectly sharp position and a perfectly sharp motion at the same time. The Uncertainty PrincipleQTM-22Quantum Wonders card QTM-23, Schrödinger’s Cat, with a glowing paper-cut illustration. It reads: An imaginary cat in a box was dreamed up to show how strange quantum rules would look for big things. Schrödinger’s CatQTM-23

Entangled

Particles that stay linked across any distance, and what that can’t do.

Quantum Wonders card QTM-28, Entanglement, with a glowing paper-cut illustration. It reads: Measure two entangled particles, however far apart: each result is random, yet when you compare them, they always pair up. EntanglementQTM-28Quantum Wonders card QTM-29, No Secret Messages, with a glowing paper-cut illustration. It reads: Entanglement can’t carry a message; the pattern only appears when both sides compare notes. No Secret MessagesQTM-29Quantum Wonders card QTM-34, Observers Don’t Need Eyes, with a glowing paper-cut illustration. It reads: In quantum physics, “observing” means any interaction that leaves a trace — no person or eye required. Observers Don’t Need EyesQTM-34

Quantum at Home

The quantum ideas hiding in lasers, clocks and screens.

Quantum Wonders card QTM-37, Lasers, with a glowing paper-cut illustration. It reads: A laser is light whose photons march in step: the same colour, heading the same way. LasersQTM-37Quantum Wonders card QTM-41, Atomic Clocks, with a glowing paper-cut illustration. It reads: One second is defined as 9,192,631,770 vibrations of the microwave that matches a quantum jump in a caesium atom. Atomic ClocksQTM-41Quantum Wonders card QTM-45, Quantum Dots, with a glowing paper-cut illustration. It reads: Shrink certain crystals to a few nanometres across and their colour depends on their size. Quantum DotsQTM-45

Quantum Frontiers

Qubits, quantum computers, and matter at its very coldest.

Quantum Wonders card QTM-46, Qubits, with a glowing paper-cut illustration. It reads: A normal bit is 0 or 1. A qubit can be in a blend of both until it’s measured. QubitsQTM-46Quantum Wonders card QTM-47, Quantum Computers, with a glowing paper-cut illustration. It reads: Quantum computers aren’t just faster computers — they tackle certain problems in a completely different way. Quantum ComputersQTM-47Quantum Wonders card QTM-50, Bose–Einstein Condensate, with a glowing paper-cut illustration. It reads: Cool atoms to billionths of a degree above absolute zero and thousands can merge into one giant quantum wave. Bose–Einstein CondensateQTM-50

Two games to play with the cards

Collapse!

2 to 6 players, ages 8 and up, about 15 minutes. You need a die.

  1. Lay six cards face up (print them, or open them on a tablet).
  2. The clue-giver rolls the die to pick a secret card, then describes it in five words or fewer, without using any word printed on it. Kids can describe the picture; grown-ups can describe the idea.
  3. Everyone counts to three and points at once. Everyone who points at the right card scores a point, and so does the clue-giver.
  4. Swap in a new card and pass the die. First to 7 points wins.

Myth or Fact?

2 or more players, ages 10 and up.

  1. The reader opens a card page and secretly picks one line: the sentence on the card (a fact) or the myth below it.
  2. Everyone gives a thumbs up for fact or a thumbs down for myth.
  3. The reader reveals the answer and reads What’s going on. A right guess scores a point.

About these cards

Are they accurate?

Each card was written to be simple without being wrong, and every card page lists where to read more, mostly the Nobel Prize website, the Feynman Lectures, OpenStax textbooks and original papers. If you spot a mistake, please tell us at [email protected].

Can I use them in a classroom?

Yes. Show them on screen, print them, or copy the explanations for your class. Please keep the web address on the card. How you can use these cards

Is there a full deck?

These 18 cards come from a 54-card deck with six groups of nine. The rest will come with a printed deck. Printed card sets