Ep. 26: Sprouts Math Game

This is a really neat game invented in 1967 by two mathematicians that was soon after published in Scientific American, where it caught fire with people all over the world. It’s a very simple game with a lot of interesting mathematics in it, and all you need are two people, a pencil, and paper.

Download the student worksheet that goes with this lesson.

1. Draw two or three dots on the paper, spaced out a bit. They can really be anywhere you want.
2. The first player draws a line that two of the spots, and makes a new spot in the middle of the line. (You can make a line joining one spot to itself also.)
3. The second player draws her line and spot also, remembering these rules:
a. You can’t make a line that crosses another line.
b. Only three lines per spot, coming to or from it.
4. The winner is the last person to draw a spot!

1 Response to “Ep. 26: Sprouts Math Game”

  1. William J. McGruder


    I thoroughly enjoyed your ‘cast about the Game of Sprouts. I have been playing the game for years (don’t recall where I first encountered it; it was either in Scientific American or more likely Games Magazine). When I was teaching in Incheon, South Korea, I showed my students how to play Sprouts. One afternoon, while I was playing one of the middle school students, his brother came up and said, “I think I’ve seen that game before; how’s it played?” Well, he was a Sprouts Shark! The “shark” was actually a champion player at the national level.

    There are a couple of different ways to play, though, basically the same but with important rule differences. The standard game is as you described in the ‘cast. There is also “misere” or “losing game” in which you win by making the opponent have the last possible move. Another variation is called “Brussels Sprouts” in which crosses (x or +) are used instead of dots, meaning each topological point can have four, vice three, line endings touching the point or cross.

    I am now teaching at an international high school in Beijing, China and have shown both my students and the math teachers how to play. A couple of the teaches have even incorporated the game into their lessons. I think the students would enjoy seeing more of your ‘cast on the subject of Sprouts variations if you were to make one, not to mention other pen and pencil math games such as Lines & Boxes or Nim. Would you consider that?

    I just discovered your videos and websites today. Great job!

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