David, Christy and Noah Swindlehurst are practicing new math at their townhome in Eden Prairie, Minn. -- minimal addition, maximum subtraction.
While the tradition for most young American families is to acquire more, the Swindlehursts are determined to get rid of as much stuff as they can spare.
"We just worked our way through four dressers, and now we're down to two," Christy said, as David reluctantly parted with some T-shirts that held sentimental value.
As 10-year-old Noah sat on an area rug, surrounded by toys and sports equipment he was giving away, his dad joked, "If you're on the rug, you're gone."
The Swindlehursts are part of a growing national movement of personal downsizers, people who are simplifying their lives -- and spending habits -- by paring down their possessions and resisting the urge to buy more.
A natural spinoff of the trend toward living green, replacing the desire to acquire with an urge to purge is catching on everywhere from the blogosphere to progressive-minded neighborhoods.
One subset, "The 100 Things Challenge," was Christy Swindlehurst's initial inspiration. By daring people to keep only 100 things, the challenge gives would-be downsizers a solid, if rather drastic, number to shoot for.
Launched by a San Diego man named Dave Bruno three years ago, the grass-roots effort has picked up a Facebook fan following and a book deal. And, yes, there's a discussion on Bruno's website about the validity of a guy who advocates shedding everything now producing thousands of books.
"Our consumer culture makes stuff very easy to acquire, but hard to get rid of," said Bruno, who isn't a hard-liner on the exact number of things others decide to keep. "Changing your behavior is not going to happen after one weekend of intense purging. The goal is to eventually free yourself from the demands of consumerism, from being stuck on stuff."
Downsizing has benefits beyond the environmental, from practical, like making housecleaning easier, to psychological -- being literally less anchored to material goods is freeing to the spirit.
The motivation to downsize is usually a combination of reducing carbon footprints, saving money, feeling more organized and passing on these values to future generations.
Sheryl Grassie wants to take up less space in the world. The Minneapolis woman raised three kids in her 3,000-square-foot home; now that they're gone, she plans to move to a space less than one-third that size. Grassie is taking things much further.
She has sold or given away most of her furniture and household goods, including former keepsakes like the good dishes she only used a couple of times a year. She's gotten rid of three-fourths of her clothes, and no longer needs her huge walk-in closet.
"We've been so conditioned to buy more, to go bigger," she said. "I'm not feeling that call anymore."
Life coach Nicole Lynskey of Minneapolis, who teaches a downsizing seminar called "Overstuffed," downscaled her possessions primarily for environmental reasons. She says the stress-reducing effect can be equally uplifting.
The same holds true for Christy Swindlehurst, a nurse, who wants to use her family's downsizing as a lesson for her son.
"The clutter stresses me out, and I want to stop making those quick runs to Target that turn into $200 worth of impulse buys," she said "But I also want Noah to learn that you can't just buy something because you want it. I don't want him getting into financial trouble down the road."
While downsizers are nowhere near approaching a majority -- retail sales did climb in October, after all -- their goals are catching on. Many young adults who grew up sandwiched between two economic downturns are showing signs of feeling very different about what defines success than their parents and grandparents did.
Generation Y is more into making friends than amassing objects, according to a 2010 Study of the American Dream by MetLife. Nearly 40 percent of millennials (people born in the 1980s and early '90s) say they already have what they need, up from 26 percent in 2008. And the number of them who feel growing pressure to buy more and better material goods has dropped almost 20 percentage points since 2006, from 66 percent to 47 percent.
But young adults aren't the only ones changing priorities. The same study found that 77 percent of all ages surveyed now see improving quality of life as being less about money than about improving personal relationships. In addition, 58 percent say they define the American dream as family and children, up from 42 percent in 2006.
That's a good thing, some advocates say, because future generations may not have a choice in the matter.
"Everybody will be simplifying their lifestyles over the next 20 years, whether we like it or not, so we might as well get ready for it," said Alliance for Sustainability's program director Sean Gosiewski. "Our overconsumption has been based on the easy availability of petroleum," which is not an indefinite given, he said.