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Mayan & Aztec Math

📋 What it is

The Maya used base-20 with just three symbols — a dot (1), a bar (5), and a shell for ZERO.

🗣️ Coach says

Across the ocean, the Maya built a base-20 (vigesimal) system — counting in twenties, likely from fingers AND toes. Remarkably, they had a symbol for ZERO (a shell) centuries before it reached Europe. With only a dot, a bar, and a shell they wrote enormous calendar numbers. It shows zero was discovered more than once.

🧠 Memory hook

Maya = base-20. Dot = 1, bar = 5, shell = 0. They had zero early and independently.

😂 Giggle

Why did the Roman student fail math?
Because they kept telling her "I" is always 1, "V" is always 5, and she could never subtract properly!

😲 Whoa!

The Maya tracked astronomical cycles thousands of years long using this three-symbol system — no calculator required.

✅ Quick check: In the Mayan system, a bar is worth 5 and a dot is worth 1. What is "one bar and three dots"?

Say your answer out loud first — then reveal.

🪄 Trick question: Did a symbol for zero only ever appear in one part of the world?

Careful — think it through, then reveal.

🧪 Try it! (2 minutes)

Write the numbers 6, 12 and 19 using only dots (1) and bars (5), Mayan-style. Guess each before you draw.

⭐ Do the round to earn your star →
🤸 Brain break: Count-by-20: count 20, 40, 60, 80, 100 on your fingers — a "Mayan handful" each time.