I know people don't usually ask. But do you mind telling me how much you make an hour?"

I felt a little uneasy asking this question at the checkout stand at the big-box store next to the freeway. It's not something you usually talk about when exchanging money for groceries.

The checker was happy to answer. "Well, I started at $9.12," she said, then added. "Last month I got a 22-cent raise. I thought it would make a big difference, but I can hardly tell. My paycheck's almost the same size."

I explained the reason for my question. "I teach math at the middle school down the street, and I want to use wages to teach them algebra."

"Well, you can tell your students there's no way to make it on less than $10 an hour," she said. "Costco's where they want to work. They start you at $10."