The Realm of Hidden Symbols

A 4th grade math adventure across seven floating islands. Decode a chess number code, solve real math, and bring a dimmed kingdom back to light.

Explore the seven islandsTry Portal Gate

No chess experience needed.

Seven islands, one journey

When children stop thinking, little lantern-like Dimmers fade the realm’s light. Solving real math brings each island back.

Chapter 1 of 3: Crack the code

Island 1 of 7

Portal Gate

The Chess Number Code, decoding and number sense

Learn the secret code and wake the first gate.

What your child learns

  • Read ten chess symbols as the digits 0 to 9
  • Build and read numbers up to four digits
  • Compare numbers by place value

Every adventure begins on this island.

Story preview

Solving math brings the island back. This is a preview of the story, not a saved game.

Portal Gate island: a stone archway glowing with blue light, with gold banners and bright crystals.

Real math, in a secret code

Each chess piece stands for a digit from 0 to 9. Every puzzle on every island runs the same three steps, and every answer ends in regular numbers.

  1. Chess 4 Math symbol for zero — King
  2. Chess 4 Math symbol for one — Pawn
  3. Chess 4 Math symbol for two — Double Pawn
  4. Chess 4 Math symbol for three — Knight
  5. Chess 4 Math symbol for four — Bishop plus Pawn
  6. Chess 4 Math symbol for five — Rook
  7. Chess 4 Math symbol for six — Rook plus Pawn
  8. Chess 4 Math symbol for seven — Rook plus Two Pawns
  9. Chess 4 Math symbol for eight — Rook and Knight
  10. Chess 4 Math symbol for nine — Queen

  1. Decode

    Chess 4 Math symbol for six — Rook plus Pawn×Chess 4 Math symbol for seven — Rook plus Two Pawns

    Read each piece as its digit.

  2. Solve

    6 × 7

    Then it is ordinary math.

  3. Verify

    6 × 7 = 42

    Check the answer in regular numbers.

  • Two ways to see every number

    Moving between symbols, pictures and digits makes children think about what a number means, not just how to write it.

  • Understanding comes first

    Equal groups come before partial products, and fair sharing before long division. There are no timers.

  • No chess needed

    Children never learn how pieces move or play a game. The pieces are simply a code for the digits.

What the seven islands teach

  1. 1. Portal GateThe Chess Number Code, decoding and number sense
  2. 2. Great Bell TowerPlace value, addition and subtraction
  3. 3. Array BridgeMultiplication, arrays and equal groups
  4. 4. Crystal CircleDivision, equal sharing and strategies
  5. 5. Royal Mosaic GardenFractions and visual models
  6. 6. Blueprint VaultMeasurement, area, geometry and construction
  7. 7. Royal PalaceIntegrated math challenges and the realm finale

Chess 4 Math is a 4th grade practice adventure to use alongside school math, not a replacement for it.

The adventure starts at Portal Gate

Choose an avatar, step through the gate and crack the first code.

Try Portal GateBack to home

Portal Gate plays best on a tablet or computer.