Book: The King's Chessboard by David Birch pictures by Devis Grebu

1. Synopsis: In The King's Chessboard author David Birch demonstrates exponential growth through the story of a king and a wise man. The story begins with a wise man who graciously serves the King of Deccan in India. The King wants to reward the wise man for being a loyal servant but the wise man wants nothing in return replying "Serving your majesty is a reward in itself." The King angrily insists that the wise man choose a way to be rewarded. The wise man then says, "Very well, sire, I ask only this: tomorrow for the first square of your chessboard, give me one grain of rice; the next day for the second square, two grains of rice; the next day after that, four grains..." Thus the wise man asks for twice the number of grains as the square before it. The King is embarrassed that he is unable to calculate in his head how many grains of rice that will end up being, but he shrugs it off and grants the wise man this reward. The granary clerk delivers the rice to the wise man every day, starting with grains, then small pouches, then sacks, then tons according to the math. Once the King is informed of this he calls forth his mathematicians to see if the rate of the grains of rice is correct. The final amount promised to the wise man is indeed 549,755,830,887 tons of rice. The wise man is summoned to the King who, now realizing that he has promised the impossible, asks if the wise man is satisfied. The wise man replies "I have always been satisfied, it was you who insisted on rewarding me."

2. The King's Chessboard explains exponential growth in real-life terms through a fable. The 64-place chessboard starts our with just one grain of rice; but by the ninth day the King owes the wise man 256 grains, and so on. This represents the doubling of products since the wise man asks for twice as much as the previous day according to the chessboard. Each day the amount is demonstrated in the exponential equation y=2^x. This story is an example of exponential growth rather than decay since x is always greater than 0 in this case. The story effectively demonstrates exponential growth through doubling.

3. Literature is an effective way to teach math since it is based on narrative rather than only mathematical concepts. The story-telling aspect of literature makes it more memorable and brings mathematics to life-applicable concepts. While I don't think that literature alone can effectively teach math concepts--there does need to be some follow-up steps to solidify the mathematical concept that is being described in the story--I do think that it is a more creative way to help people learn math.