Traffic lights

Age
7 to 11
Challenge level
filled star filled star empty star
Exploring and noticing Working systematically Conjecturing and generalising Visualising and representing Reasoning, convincing and proving
Being curious Being resourceful Being resilient Being collaborative

This month's new game was designed to be just about the most accessible game imaginable. I wanted a game which could be explained in a few seconds, and which would take less than five minutes to play. There was a further requirement that it should not require any fancy equipment. Finally, of course, it should be non-trivial to play.

I hope you'll agree Traffic Lights meets all these requirements. It's been used with children as young as six or seven, and yet computer analysis has shown there's no obvious winning strategy. Furthermore, like last month's game Femto, there are a wealth of possible variations to discover and try out.

Rules for the BASIC GAME

  1. Traffic Lights is for two players.

     
  2. It uses a 3x3 squared board. At the start of the game the board is empty.

     
  3. Counters: the game needs about 6 red counters, 6 orange, and 6 green.

     
  4. The players take turns to play.

     
  5. When it is your turn to play you must either:

    * place a red counter in an empty square, or

    * replace a red counter already on the board with an orange one, or

    * replace an orange counter already on the board with a green one.

  6. You win by completing a line (row, column, or diagonal) of three counters all the same colour. (Clarification: it doesn't matter who placed the first counter(s) in the line - it's the third counter of the line which determines the winner.)

     

 

If you play several games of the basic version you may find that - even though the computer didn't find a winning strategy it also failed to point out that there is a factor that ought to limit its interest after a while.

 

VERSION 2

So you may want to move on to VERSION 2. This game modifies rule (2), so that your 3x3 board has an additional 3x1 strip placed against one edge, and the board now becomes a 4x3 board.

VERSION 3

For many people version 2 is just about right, but for real addicts there's more to come. If you like your games to make your head hurt, then try VERSION 3. If you made your board for version 2 in the form I described it, you have a two-piece board (a 3x3 square and a 3x1 oblong. In version 3 players have a new option; instead of placing a counter they may move the strip (and any counters on it). The strip may be turned through 180 degrees, or slid (and turned if preferred) to line up against another edge of the 3x3 section of the board. All the other rules are unchanged, so you're still trying to complete a line of three pieces all the same colour.

Of course, I expect that people will be happy to knock up a home-made set for themselves, but Traffic Lights is available in a published version produced by Fiendish Games, so if you're stuck for an idea for a birthday present I can send sets for just £3 plus 50p postage costs.

Good luck!

Alan Parr