I found the rules to this game on Steve Baker's website. There's a nice Java implementation of it here.

• Graph Racing
• Graph Trees

Graph Racing

The playing field is simple: a sheet of wide graph paper. Someone draws a race track on it with a start/finish line. Then it's off to the races.

The rules are also simple and copied verbatim from Steve's website.

• RULE 1: Your 'car' is always at the intersection of the lines on the squared paper - not inside the squares. As you drive around the track, you draw lines showing where it goes using your own colour pen or pencil.
• RULE 2: Players take it in turns to move - the youngest person plays first.
• RULE 3: First person to make it all the way around the course once wins.
• RULE 4: Each turn, you car can either move the same number of squares in the same direction as it did last time - or it may move one square more or less in either North, South, East or West directions than it did last time.

I like a fifth rule added by the Java implementation.

• RULE 5: If your car ends up outside of the track at the end of its move, it's reduced to a single move in any direction until it re-enters the track.

Just to keep munchkinism from happening, I'd also add the following rule:

• RULE 6: Checkpoints should be drawn across the track on the same line as the start/finish line where the track overlaps the line. All of these checkpoints must be crossed in order to win.

Steve has a great page to use for reference; I don't see any particular need to copy it word for word.

Note that players can go either way around the course. The first player to act should consider who's following and which direction to start. Following players can mimic the lead players without too much difficulty. Similarly, if two players go opposite directions, they can follow each other's tracks once they reach the halfway mark back to the finish line.

Graph Trees

This is based on a game that we played at my elementary school. We didn't have any sort of elaborate rule set. There was just a communal understanding of what moves were legal and what moves weren't. After learning about graph racing, I think I can translate it into a simple set of rules.

Graph Trees is a game of territory similar to Go. The object of the game is control as much territory as possible. The playing field is a sheet of graph paper. With two players, each player starts on opposite sides. With four players, a player starts on each side. Movement is the same as Graph Racing with the following exceptions:

• Tracks may NEVER cross.
• During a player's turn, the player may opt to start a new track off of any node on that player's previous track. Movement from this node is the same as starting movement. However, a player may not start a new track in the exact same direction as a previous track.

For example, assume the red player starts at the bottom of the following tree. Having gone as far as he can, the player must start a new track. Nodes in green are valid moves; nodes in orange are invalid moves.




In elementary school, the game started off as a 'trap your opponent' sort of game, leaving your opponent with no legal moves. However, it became obvious that a stubborn opponent could continue to make moves, even after the outcome of the game was clearly decided. This version of the game decides the winner based on territory. Territory is determined by number of intersections enclosed by a player's track. It is often not necessary to fully exhaust a player of all legal moves to determine a winner. Just like Go, the game is over when the players agree that there is a winner.

Note that it is necessary to keep track of the 'velocities' of each track, since these 'velocities' will be used when the player decides to make a move on that track again. This usually isn't a problem except with new tracks; we used to put faint hashmarks through the first path of a new track to help us keep it straight.