I tend to incorporate a lot of math things into our everyday lives, for instance last year, we had a behavior/allowance chart that was tally based. It's been a natural thing to do b/c DS7 is math accelerated and is and always has been a little engineer. The kids get allowance so they can practice counting money and learn its value. DS is also asthmatic and needs medicine daily. So, last year, when counting got boring, we skip counted in various ways -- 2s, 3s, 5s, 10s (and counted in other languages). That kind of stuff. But DS actually was able to read charts and graphs, including those where a key would indicate a symbol is equal to a larger amount than 1.

He's got an older brother and I can't recall if DS5 was around when I was talking with DS7 about checking the key to make sure his answers are right. Often, DS5 will be within earshot when homework is going on. He can add and subtract single digits. He surprised me a couple of weeks ago when we were playing Monopoly b/c he kept mental calculations going of how much money he had as he earned and paid for things. And last year, when a preschool teacher tried to get him to paint big strokes rather than his very carefully painted lines, DS5 looked at what she'd done with the paintbrush and told her she'd drawn an infinity symbol and then went about painting the way he wanted.

I know that's a long answer. But I think our lives are just too fluid to fully figure it out!