This is what people always say when they learn that I'm the mother of three teenagers and a tween - "Whoa ... I guess you spend a lot of time hearing how stupid you are."

Usually the people who say this also are the parents of teens, and the comment comes as an attempt to bond over our presumed mutual suffering from the ill effects of our adolescent's bad attitudes.

I heard a comment like this recently at the doctor's office, when I mentioned that I have a 14-year-old son. "Oh, my kid is 15," came the reply. "I never knew how dumb I was until now. But that's just a teenager for ya. Right?"

Decision time: Do I say, "It is a dumb adult, indeed, who lets a teenager speak to him as though he is a potted plant," or do I smile and nod in deference to the needle he holds in his hand?

I punt. "Well," I say, "I never bought into that myth about teenagers naturally being snarky and disrespectful. I think that idea shortchanges teens. They're actually able to be quite pleasant."

The doctor doesn't say anything, but instead stands there with the needle. "Or maybe we're just lucky," I add.

"You are," the doctor says. Stab.

Where is it written that teenagers must necessarily speak to their parents as if we were pond scum or, worse, middle-aged adults?

Everywhere, it turns out. Pick up a parenting magazine or Google the words "teen attitudes" and you'll find a million "experts" claiming that hormones, coupled with an age-appropriate desire for independence, understandably causes teenagers (and even tweens) to treat their parents rudely.

Sorry, but I don't understand. Or maybe I do, but what I get is that American culture has created a sanctioned state of immaturity and selfishness, mired in emotion and punctuated by back talk, conveniently labeled "adolescence." And now we learn this state of adolescence may extend into the early 20s. Great. Continued...