Classic Games
CKSTEM Reversi Arena
Learn Reversi (Othello) — the game where the math IS the strategy. A discovery-first Academy of 8 lessons and 192 guided puzzles (the greedy trap, corners, mobility, parity, the endgame) where you learn each idea by SEEING it happen, a bot ladder from Greedy Gus to The Closer (the strongest Othello engine), pass-and-play on one device, and live class arenas where the whole class battles head-to-head on a live ladder. Teaching first — free, no login.
For Educators
Built for the classroom
Strategic thinking in a game where the mathematics is visible: why grabbing the most discs early backfires (greedy ≠ best), why corners can never be flipped (an invariant), mobility (keep your options open while shrinking your opponent’s — the minimax idea behind game AI), stable discs, and endgame parity (odd/even counting, the Nim connection). It is discovery-first: every idea is something the student SEES happen on the board and then names — never a rule told up front. After each solve a “Why this works” note explains the idea, so even a lucky guess teaches something.
Grades 3 to all ages. Three board sizes (gentle 6×6, classic 8×8, big 10×10) and three ways to play. Nothing is locked — the Academy suggests an order but every lesson is open from the start.
Three ways to play
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CKSTEM Reversi Academy (guided practice)
Eight lessons and 192 guided puzzles laid out as a numbered ladder (the Greedy Trap → corners → mobility → parity → the endgame). Hints help you SPOT the idea without giving away the answer, and a “Why this works” note follows each solve. You master a lesson by solving its puzzles AND showing the idea in a real game.
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Play vs the bot
Climb a seven-step ladder from Greedy Gus to The Closer (powered by the strongest Othello engine) on 6×6, 8×8, or 10×10. Each rung removes one idea, so a true beginner can actually beat the early bots.
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Pass & Play (solo/home)
Two players share one device — the board flips between turns. No login, great at home or on one shared laptop.
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Host a live arena
Open a room on the projector; a 4-letter code + QR + join link appear. Pick a board (6×6/8×8/10×10) and timers, then watch live mini-boards fill with discs as a ladder climbs. Students play best-of-2 duels (each goes first once — that swaps the Dark advantage, so it’s fair); the odd student out plays the beatable Greedy Gus bot so nobody waits.
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Join on any device
Students enter the 4-letter code (or scan the QR / open the link) on a laptop, tablet, or phone and get matched against a classmate. When a match ends they’re instantly re-paired — no waiting, no elimination.
Run a live class in 5 steps
- Open CKSTEM Reversi Arena and choose Host an Arena — pick the board (Small 6×6, Classic 8×8, or Big 10×10), the session length, and the per-move timer.
- Share the 4-letter code / QR / link; students join on any device.
- Hit “Open the Arena”: students play best-of-2 duels — they swap who goes first (plays Dark), so it’s fair.
- Watch the live ladder climb and the mini-boards fill on the big screen; an odd student out plays the beatable Greedy Gus bot so nobody sits out.
- When time’s up the podium crowns the ladder. No accounts — the ladder lives only while the room is open.
Tip: host on a laptop or projector (the big screen shows the code, QR and leaderboard); students join on their phones or laptops.
