Go to the craft store and buy a bag of clear blue stones. Or go to the beach and find 30 smooth pebbles. Put them in a jar. These pebbles will be the start of a surprisingly effective behavioral system.

Think of a behavior you want to extinguish. Back talk? Okay, begin by forgetting everything you've tried (unless what you've tried has worked, in which case you might want to stop reading and go find something else to do). Here's your new plan:

At the start of each week, your child will get 30 stones in a jar. Each time she talks back (uses a rude tone, sasses, argues when you've asked her to stop) calmly say, That will cost you a stone. During the first week, if your child immediately stops, nothing else needs to happen. If she continues, walk over to her jar and calmly remove one stone. That's it. At the end of the week, your child will get one point for each stone over 15 that remain in the jar. If she has 18 stones left, she gets 3 points (18 minus 15). If she has 27 stones left, she gets 12 points (27 minus 15). If she has 9 stones left, she gets zero.

After that first week, do away with the warning. If she sasses you, she loses a stone (make sure you tell your child about this, first). Continuing to use 15 stones as a base is important; your child's behavior won't change unless she is putting forth effort to hold onto her stones. Fewer than 16 stones shows very little effort.

Decide on a menu of rewards based on points – 15 points might earn a trip to the bookstore; 25 points (accumulated over several weeks) a visit to the local SPCA to pet the cats; 40 points a sleepover with a friend.

Some important factors:

  1. Your child should lose only 1 stone at a time. Don't retaliate with You just lost another stone if your child sasses you when you take the first one. Upping the ante in this way will quickly wipe your child out, rendering the system useless. If you take a stone and your child keeps talking back, shift to a different system for setting limits. 1‑2‑3: Magic is particularly effective (First infraction, say That's one; if child continues, say That's two; if keeps going, say That's three and deliver a consequence such as time-out or the brief loss of a privilege).
  2. Keep your tone neutral (this is hugely important).
  3. Don't engage in the specifics of what your child is saying. When she talks back, simply state That will be a stone (eventually shortened to Stone).
  4. Explain the system to your child before beginning. Focus on the benefits to your child: less yelling and the opportunity to earn cool stuff.

The beauty of this system – which works on back talk, swearing, complaining, whining, begging and other forms of negative persistence – is that it helps children modify negative behavior with relatively little fuss. What could be better?