Three in a Row is a two-person game played on a 3 x 3 square grid using six markers. Each player needs three markers which can be easily distinguished from those of the other player. Coins, beans, buttons, checkers, math chips, or any other small manipulatives will all work well. The object of the game is to get three markers in a row horizontally, vertically, or diagonally. Players begin by taking turns placing their markers into empty spaces on the grid one at a time. Once all six markers have been placed, if neither person has three in a row, play continues by sliding the markers from one square to another. Markers may slide into any adjacent empty space horizontally or vertically, but may not move diagonally. The game ends when one player succeeds in getting all three of his or her markers in a row horizontally, vertically, or diagonally, or a stalemate is reached.
A stalemate is possible when one or both players simply move the same marker back and forth between two spots. If this begins to occur with some frequency, a rule can be made that you are not allowed to move your marker back into the spot it just vacated until one round has passed. This will prevent students from repeating the same move over and over, keeping the game from progressing.
As students play this game, they will soon discover that the strategy lies not only in how you move your markers once they are on the grid, but in the original placement of those markers. After several rounds have been played, encourage students to stop and evaluate the strategies that they are using. Which player is winning more often? What is that person doing differently? Are there certain moves/locations that will always let you win?
Six markers, three each of two kinds
To get three markers in a row horizontally, vertically, or diagonally.
1. Each player has three identical markers. Players take turns placing their markers into any empty square in the grid.
2. If neither player has three in a row once all of the markers have been placed, the game continues by sliding the markers.
3. Markers may slide horizontally or vertically into any adjacent empty space. Markers may not move diagonally.
4. Play continues until one player succeeds in getting three markers in a row.
We hope you and your students have fun playing this new game. If you have any questions or comments about this or any other Puzzle Corner activity, please feel free to leave a comment below.