Color Caller
How it works
Color Caller is a 2-player game. Here's how to play:
You play with red and blue chips
The game board has a big circle. To start, there are some chips inside the circle and some extra chips outside the circle
Before players start to make moves, one player (the caller) chooses a color (red or blue)
On each turn, you take 2 chips out of the circle and put 1 chip in:
- If you take out 2 reds or 2 blues, you put in 1 blue
- If you take out 1 red and 1 blue, you put in 1 red
The 2 players continue taking turns until there is only 1 chip left in the circle
If the color of the last chip matches the caller's color, the caller wins. If not, the other player wins
Could you guarantee that you win this game every time if there are 3 red chips and 2 blue chips and you are the caller and you go 1st? If so, what color would you call? What if there are 4 red chips and 1 blue chip? Can you guarantee you win no matter how many red and blue chips there are if you are the caller and you go 1st?
In this activity, students work together to figure out how to beat a facilitator with different combinations of reds and blues if they are the caller and they go 1st. If they master this version of the game, they also explore a variation with 3 colors instead of 2.
Why we like this activity
It’s fun! Students enjoy playing the game and figuring out how to beat the facilitator.
It helps students to develop logical reasoning.
It helps students to develop numerical reasoning.
It requires students to engage in mathematical habits of mind:
Using logic and finding and using strategies to win as the caller
Looking for patterns when trying to figure out how to win with different combinations of chips
It has a low floor and a high ceiling: Students can start playing the game by trial and error, but figuring out how to guarantee you win with any combination of chips is challenging!
