Though, as a story, the conclusion he draws is pretty self-congratulatory and bothers me a bit. The substrate on which you implement an algorithm like arithmetic doesn't really speak to whether you "know numbers." It's like the high schooler thinking being very good at computing integrals makes you good at math.
This is more of an interface problem I believe.
(A real magician would also work to make sure that the kids thought they chose the problem, but the choice had already been primed for them.)
then again, they wouldn't have let me in that class in the first place.
This is obviously false, and I don't really understand the point of saying this.
Plus, the benefit of using a computer is that computation is effortless, letting you use more of your brainpower on actually interesting problems rather than something that is easily automated.
And then she chose a question from the book, had one of us start typing, and she started at the board solving the same thing.
She finished first. Not by much, and obviously the calculator is the faster choice more often, but she finished first.