I observed my math-genius four-year-old daughter 'solving' the problems I'd given her. My son did the actual math on the abacus and told her to count the beads. He'd keep telling her to count again when she got it wrong. She's extremely bright, but I should have known that he'd find a way to steal her thunder. I had the computer ask her what's 1 + 1. She said 11. I figured that was a joke. 2 + 2? Twelve.

A few days later, he began making 'books' for her, whose pages feature several math problems, and answers in jumbled order on the same page. She draws lines to connect the problems to the answers.