The only winning move is not to play

While riding in the car, my youngest son is not always good at keeping himself occupied. One way I help him (and me by keeping my mind sharp) is to play tic-tac-toe with him. But, instead of passing a piece of paper back and forth between us, he keeps track of the game on paper and I keep track in my mind. By numbering the grid squares between 1 and 9, I can call out the square number and he applies my X or O to the paper.

I think he's broken the code though. :-( Perhaps he's got this tac-tac-toe book memorized! It's a whole new kind of "Choose your own adventure." I loved those books!