I don't know why this came into my head this morning, but it did, so I will share. When I was little, my mom and I were at Wal-Mart (I believe) looking at juice. I tried to pick up one bottle or thing of juice boxes or something since it was the "cheapest". Mom showed me how to divide the amount by the ounces of juice or boxes of juice, whichever. That showed a different bottle/juice box set was cheaper. I wasn't very old, but old enough to do division. Maybe 3rd grade? There was a man in the aisle with us who kept looking over at our consumer lesson and laughing. He might have said something to my mom about that's a good thing to teach her, or some such.

Now most of the stores I shop at figure on the label the price per ounce (or whatever unit). It's in small letters and you have to look for it, but it is there. I appreciate that. And I appreciate my mother teaching me to shop.