Frumpy Middle-Aged Mom: You know there are teenagers in the house when…

I have a friend whose children are old enough now to strike fear into the hearts of their mother, as she dreads the coming transformation from adorable kid to hulking, hairy creature from the black lagoon.

Since my kids are already well into this transition, Barb views our family like a big, messy science experiment, peering at us as if we were all in a petrie dish, to see what she can learn to prevent future similar disasters in her house.

I have explained to her that these years are exactly like high school football Hell Week, except they last longer, cost a lot more money and go on well into the night. The yelling, the bruising, the perspiration, the mental anguish, the stress, the exhaustion, the momentary exhilaration are all the same.

Barb is wondering exactly when this period of adolescence will kick in, presumably so she can have the Prozac ready.

Now, even though I bitterly resent her because she's thinner than the day she got married, I decided to give her some warning signs, in case she wanted to get in the lifeboat and flee.

So, Barb, you'll know you have teenagers in the house when:

• The balance of power shifts, and you discover you now have to negotiate with the rebel factions instead of just brutally suppressing them.

• There's a big shadow in front of the refrigerator and you realize it's a kid, holding the door open and peering inside as if something new has magically appeared in there in the past 20 minutes.

• You open said refrigerator to discover the only remaining milk jug is empty and has no cap on it.

• Certain bedrooms in your house start smelling eerily like an NFL locker room after a Monday night game.

• You realize you're living with alien creatures who know everything and think you're stupid. They contact their mothership by rolling their eyes and mumbling behind your back.

• There is never any hot water left in the shower, even at 4 a.m. On the plus side, there are always plenty of towels available. On the floor in a wet heap.

• A child runs into the living room twitching, in a state of wild-eyed speechless panic, and just when you're about to call 911, she gathers enough wits about her to ask if you've seen her phone because it's missing.

• Your kids spend more time in front of a mirror than the prima ballerina of the Bolshoi Ballet.

• The house is silent, the doors are closed, but all the extension wires leading into their rooms are red hot.

• The dirty dishes are carefully piled on top of the dishwasher.

• Your kids flinch like you're covered with sewer slime if you try to make body contact with them.

• You always have someone around to show you how your new phone or computer works.

• You have long soulful chats with any teenager except your own child, who refuses to tell you even which high school he is now attending.

• The car radio mysteriously loses the power to play anything but pop or hip-hop stations designed specifically to make your teeth ache like you just got a root canal.

• You get up in the morning and your kitchen looks like a kindergarten class had a party in it at midnight.

• Mood swings — yours, not theirs. Your feelings veer between relief that they're out of the house, and fear that they're doing something idiotic away from you that will ruin their future lives.

• "Not now, Mom," becomes the answer to every question, even when there's ice cream involved.

• There are several pairs of shoes by your door that look like water skis and you find shoe prints on the wall, but head-high.

• Your kids suddenly lose their hearing. (Hello? Hello? I'm talking to YOU!)

• There is nothing to wear, even though their closets look like a boutique.

• Your water bill is up, your patience is down, your kids are never full and your wallet is always empty.

And thanks to colleagues and readers Rebecca Allen, Bret Colson, Marilyn Davis, Anne Dugan, Jane Gillespie, Amy Gold, Leslie Knapik, Cindy Merino, Cindy O'Dell, Jill Olsen and Pam Powers, who made it out alive to share their stories.