Car Conversations

My kids like math. I think it's partly because I like math, and partly because we've made it such an ordinary part of our every day conversations.  Especially in the car, when they're a captive audience. :)

Today on our drive to the babysitter, my son (who just turned 12) asked me how much I weigh. He then figured out how much water I should be drinking per day; I've told him before that the recommended amount is 1/2 of your body weight in ounces.

This turned in to how many bottles of water I should drink per day (I have a 24 oz bottle that I use) and how many ounces I actually drink per day.

It was fun to hear him think through the steps.
"So, if you drink 4 bottles per day, that's...
20 times 4 is 80.
4 times 4 is 16.
So that's 96 ounces."

And then I asked him, "What if my bottle was 25 ounces??
Him: 25 times 4 is 100.
Me: But how much less is my bottle?
Him:  1, so 4 times 1 is 4 and 100 - 4 is 96.
Mom, that's the distributive property!

(I swear, I didn't prompt him for this at all.)
Him:  25 times 4 minus 1 times 4
Me: Did you use the distributive property before, too?
Him:  20 times 4 plus 4 times 4.  I guess I did!

Ah, sweet music to my ears. :)