Before you start
Most popular
Card Table You’re dealt a hand — build a run, make a matching set, add two to ten, or find the highest and lowest. The number sense behind every card game. 
Magic Workshop Predict how a card trick ends BEFORE the reveal — then find out why it was never magic at all. It’s forced by arithmetic. 
Card Duel A head-to-head kit round for 2–4 players — one device or an online room by code. Highest first-try score wins. 
Mixed Practice Shuffles questions from the kits you’ve played, brought back when they’re ready to review — great for making it stick. All activities
Play & explore
Card Table Build runs and sets, add to ten, find highest and lowest — the number sense behind every card game. Magic Workshop Predict-first: how does the trick end? Then see why it was never magic — it’s arithmetic. Force Forge Now BUILD your own self-working trick: chain steps from a palette and the engine live-checks whether they force the same answer no matter the secret start. Gilbreath's Riffle Alternate the colours, cut, riffle any way you like — every pair STILL holds one red and one black. Predict the invariant, then see why it is forced, not luck.
Practice & play
Practice the concepts
All 16 kits
Kit 1: Card Game Basics Kit 2: Probability and Card Math Kit 3: Strategy and Game Theory Kit 4: Magic Tricks and Mathematics Kit 5: Advanced Card Games Kit 6: Card Trick Performance Kit 7: Advanced Probability Kit 8: Game Design and Creation Kit 9: Advanced Probability & Combinatorics Kit 10: Game Theory & Decision Making Kit 11: Card Game Design & Mechanics Kit 12: History & Culture of Card Games Kit 13: Cross-Topic Connections Kit 14: Real-World Applications Kit 15: Misconceptions & Reasoning Kit 16: Advanced Synthesis
For grown-ups — progress report →
More ways to play
😄 Brain break
Meet the cast — the characters who teach this
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The Finesseur Finesse (force an opponent's high card via positional play; bridge / hearts / spades) -
The Squeezer Squeeze (force a discard that gives up a winner; advanced bridge + hearts) -
The Endplayer Endplay (throw opponent in to force a losing lead; bridge / hearts / whist) -
The Counter Card-counting / pip-tracking (track played cards to deduce remaining hands; gin / bridge / blackjack-style) -
The Long-Suit Suit establishment (set up a long suit to run for tricks late in the hand; bridge / whist / spades) -
The Bluffer Deception under uncertainty (poker betting; representing a hand you don't have) -
The Discarder Strategic discard (hearts: avoid points; spades / gin / rummy: shed dead wood) -
The Trumpkeeper Trump management (when to ruff, when to hold; whist / spades / euchre / pinochle) -
The Forcer Magic forcing (the spectator "freely chooses" the card you intended) -
The Shuffler False-shuffle / stack management (control card order while appearing to randomize; mathematical card magic)
Ensemble stories — the cast together