Once a child is capable of reading and doing math on about a fourth grade level, he might enjoy supplementing his regular math program with some mathematical literature. Unlike simple math books aimed at younger readers, these books tend to cover multiple concepts in greater detail. I've compiled a short list of my favorite titles.
Norton Juster's story of The Phantom Tollbooth is a modern day classic illustrated by Jules Pfeiffer. What kid can resist the tale of young Milo and his trip into the strange lands beyond the tollbooth? The conflict between the rulers of Dictionopolis and Digitopolis can only be resolved with Milo's assistance. Juster's memorable characters make this novel shine.
A more recently published novel about math was originally written in German. Hans Magnus Enzensberger is the talented author of The Number Devil, A Mathematical Adventure. In this story, twelve year old Robert dreams of a number devil who teaches him to appreciate the beauty of higher mathematics. Quirky cartoons and diagrams are a nice complement to the tale. This 250 plus page novel is for strong readers and math oriented kids who will not get frustrated with advanced concepts. Topics introduced include topology, proofs, irrational numbers, and more.
The Math Book for Girls and Other Beings Who Count is a picture book and not a novel, but it is aimed at the mid to upper elementary crowd. This book is a great way to show kids that math can indeed be both fun and useful. It's an interesting blend of fiction and non-fiction. There is a central story, based on interactions between a girl and a tiny “math fairy” named Nora. Nora gives overviews of concepts such as symmetry and probability. The real life math sidebars demonstrate how scientists and others utilize math in their daily work.
Theoni Pappas is a wonderfully creative teacher with a host of books and math games to her credit. She is the author of Penrose the Mathematical Cat, Fractals, Googols, and Other Mathematical Tales, and Math for Kids and other People Too, among others. Her enthusiasm is contagious and her writing is a pleasure to read. Her work is probably best suited to middle school level students.
Larry Gonick is best known for his cartoon history books, but he's also written and illustrated The Cartoon Guide to Statistics. Gonick's amusing cartoons are terrific for visual learners, and with this book, he's even found a way to make statistics appear exciting!
Finally, don't underestimate G is for Googol: A Math Alphabet Book written by David Schwartz and illustrated by Marissa Moss. This is far from an ordinary alphabet book. Schwartz brings together a wealth of mathematical information for strong independent readers. A is for abacus, F is for Fibonacci, and K is for Konigsburg! This book is informative and entertaining.