“But the left hand’s the boss!”

When Corina Silviera was working toward her PhD at the University of Southampton in the UK she came up with a written number recognition game. 

The game was played with a pack of plain cards, each with one of the numbers 1 through 100 written on the card:

Corina chose a small group of 5 year olds to play a game with these cards.

First one of the children shuffled the cards and dealt 4 cards to each of the children present.

Then the children took turns in laying down one of their cards.

The winner of a round was the child who laid down the highest number card.

An important aspect of the game for Corina was to let the children figure who won: her aim was to understand how they knew which card had the largest number.

Of course there’s an element of strategy in this game in that if someone lays down a card that’s larger in number than all your cards then, to optimize your chances of winning future rounds, you should lay down your lowest numbered card.  However, generally the children did not do this.

In one round the children laid down the following cards:

The child who put down the card with the number 62, scooped up the five cards and declared he had won the round.

Corina pointed to the number 62 and said: “How do you know this is the biggest?”

“Because there’s a 6”, said the boy who scooped up the cards, pointing to the 6 in 62.

“But this card”, said Corina, pointing to the card wth the number 29, “has a 9.”

The children looked at each other, and then at Corina, almost with pity in their eyes that an adult would not know such an obvious thing, before announcing:

“Yes, but the left hand’s the boss!”

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This was an example of the regularities in children’s engagement with numbers, even those they could not name, that Corina was seeking to uncover.

None of the children in the group knew that “69” was read as “sixty-nine” nor could most of them count that far, yet they had picked up on a regularity in the place value representation of numbers in the adult world.