Kate (Age 9, Grade 3) and I were in the grocery yesterday afternoon. We were buying potato chips … the requested treat of her sister who had stayed in the car to read Harry Potter for the umpteenth time.
Me: Which bag of chips should we buy – the smaller bag (8.5 oz.) or the larger bag (13 oz.)?
We examined the labels, and I showed her the per ounce price for the smaller bag in the bottom left corner, both forgetting that her experience with decimals is limited and feeling guilty that we were just using the given rate instead of talking about how it was calculated.
K: 34 dollars and 9 cents per ounce?!
Me: Oh – we read that 34.9 cents. But for now let’s call it 34 cents per ounce (I didn’t think getting into a conversation about rounding was our best bet at this point.)
K: And the other is 29 cents.
Me: So which one should we buy?
K: The small bag.
Me: [I was surprised by her answer. Kate has been comparing numbers successfully for a while now.] Why did you choose the small bag?
K: Doesn’t it taste better if it is more expensive?
We proceeded next to the cans of green beans. And since our grocery hasn’t had organic green beans now for over a year, we bought the next most expensive offering on sale at 10 for $10 instead of the others regularly priced at $0.49 each … I wonder where she learned that some things do taste better if they are more expensive?