Reading in math class: The Number Devil
Do I really have high school kids read a math story book? Yup.
The Number Devil is one hell of a book. And I have enough copies for three classes. We read it, slowly, over the course of a few weeks. If/when they lose interest, I’ll take the books away. Twelve chapters – we could make it through 3, or 6, or the whole thing.
The kids tell me it’s written on a 3rd or 4th grade level. Some have already read it. No matter. They haven’t read it with me.
Basic plot – kid hates math. Has bad dreams. The Number Devil comes to him in his dreams, shows him “different” ways to think about math, and the kid ends up liking and getting good at math.
Now, we’ve just struggle through factoring, algebraic fractions, and their applications. In other words, the toughest stuff in the course. We are graphing – which is a nice breather. And the Number Devil is another breather. So what that it’s numbers and not algebra. Numbers can dance. And these kids are just about ready for dancing numbers.
The math all looks easy, but there are twists. In the first chapter he uses lots of 1’s to make other numbers. So what? 1 x 1 = 1, 11 x 11 = 121, 111 x 111 = 123231, and the kid says what happens if you use eleven 1’s times eleven 1’s and the pattern breaks, and the kid admits that he just guessed a lot of 1’s, and the Number Devil goes berserk, and explodes.
So easy to miss. I got my students to catch the use of a counter-example, and to figure out that the Number Devil was angry because the guess was unnecessary – the pattern breaks down in a predictable way. And then I lectured about Peano, and axiomatizing arithmetic as the Greeks had geometry, and that forest of 1’s and Peano’s postulates and mathematical induction… and I think I hooked the kids on lots of easy math and silly stories, and lots of deep hidden math. I talked just a bit about Berlin and Hilbert, and we have a few copies of Victor Katz’s history in the back, and some boys were dipping into it. They do learn when I give them a break.
We’ll be up to Chapter 4 next week. I’ll see how long it lasts. In the meantime, I gave them their only related assignment today – to write their own, extra chapter of the book. In character. One to three pages. Already one girl asked if she could write longer.