I'm in a modestly upscale suburban mall, tagging along behind my 15-year-old daughter, Rachel, and two of her friends. Striding forward in a way that is at once jaded and purposeful, the three girls dismiss most of the stores on first glance. "That store is for old people," explains one of them. Another store has "cool stuff" but is overpriced. Yet another has "good bargains," but it's too much work to find them in the sea of "junk" in which they're buried. The girls deign to stop in the Gap for a minute but roll their eyes at a young salesperson's suggestion that capri pants are hot. "Sure, if you want to look like you're trying to be trendy," says one of them, mercifully out of earshot of the perfectly helpful Gap employee. Back in the mall corridor, I veer toward the telescopes in the Discovery Channel Store but find the girls staring after me in horror. "I would never -- ever -- set foot in that store of my own free will," says one.

In five years, some 25 million U.S. teenagers will be roaming malls, downtowns, and Web sites. They'll be a free-spending bunch if today's teens are any guide. According to Teenage Research Unlimited, teens now spend an average of $100 a week, and last year they spent a total of $153 billion -- a number that's been growing at 6% a year. Forget about baby boomers; from here on out, Generation Y is the market to crack.

Unfortunately, most of us feel we'd have a better chance of achieving a breakthrough in quantum gravity than we would of figuring out how to reliably connect with teenagers. As tens of millions of Americans are discovering, even being the parent of a teenager doesn't exactly lift the veil on the teenage code. On the contrary, if the average teenager seems mysterious and somewhat aloof, your own teenager seems to be channeling on an intergalactic level. (Outside my home I have to remind myself to answer to names other than "Dork" and "Loser.") What chance do businesses have?

That's a question for the experts. Fortunately, I tracked down two who nicely filled the bill.

A mosh pit is the squash-court-sized cleared area in front of the stage at a rock concert where seemingly crazed concertgoers hurl themselves at one another. It looks like a life-or-death rugby scrum, except that bystanders are fair game. I could have sworn I was a safe 15 feet away from the pit at this concert, but its boundaries have apparently crept through the crowd to envelop me. I can feel the vibration in my teeth from the nearby impact of bodies.

Turning into the crowd behind me in my struggle to move away, I bump into an 18-year-old built like a professional wrestler. He has a girl on his shoulders, who, I am mortified to observe, is taking off her top. I have the feeling that I'm going to be simultaneously arrested and crushed to death.

What on earth am I doing here? Well, I am seeking the counsel of the two men who are onstage 100 feet away, guitars slung jauntily to the side as they take a break between songs. At the moment, one of them is spitting a stream of water -- I'd like to think it's water -- high into the air; the other has picked up a bra that a fan threw onstage by way of tribute and has fastened it around his face to produce a surprisingly good imitation of a housefly.

Meet Blink-182. They have agreed to answer for me one of the greatest questions facing the business world today: What do teens want?

If anyone could wring a profit from the sort of behavior I witnessed in the mall, it would be Mark Hoppus and Tom DeLonge. After all, a significant portion of the world's teens have already accorded them demigod status, not to mention a big chunk of their allowances. Hoppus and DeLonge are the two founders and lead performers of Blink-182, the pop-punk trio whose recent CD, Enema of the State, is approaching the 5 million mark in sales. Both are also enthusiastic and ambitious entrepreneurs. Besides having played an active role in painstakingly building Blink's business side (think major concert concession sales) and managing other bands, the two have founded a popular clothing and accessories Web business called Loserkids.com. Started with a onetime investment of $20,000 from the two, Loserkids has reinvested its profits to grow its inventory to be worth $500,000. (Third band member Travis Barker, a relatively recent addition to the group, owns a leather goods and accessories store in Riverside, Calif.)

Hoppus is a perpetually wide-eyed and slyly grinning 28-year-old who favors ankle-length cargo pants worn low enough to show off his colorful boxer shorts. The amiable and slightly laconic DeLonge, 24, sports tattoos up and down one arm, a lip ring, and a baseball cap worn backwards, with dyed hair sticking out from underneath it. I spent the better part of a day with them at Hoppus's spacious new home overlooking a softball field in a tony San Diego suburb. When Hoppus wasn't directing workmen or joining DeLonge in taking part in an apparently endless stream of brief on-air phone interviews with disc jockeys or discussing tax-reduction and life-insurance strategies with their advisers, the two provided some rules of thumb for relating to teens, in malls and elsewhere.

Blink-182 rule #1: Teens don't like what they sense they're supposed to like.

Consider the way my daughter and her friends tended to turn up their noses at most of what was presented to them at the mall. It's not that teens indiscriminately spray disdain at any nearby target, as often seems to be the case to the rest of the world. Rather, says Hoppus, teens have an exquisitely sensitive allergy to the hype and manipulation that -- let's face it -- underlie most of what passes for marketing. "Teenagers put a lot more time and effort than the rest of us into knowing what's real," explains Hoppus. "They can see what's fake right away."

Hoppus believes that most businesses that target teens come off as phony, condescending, or disrespectful. "Teenagers can tell that a commercial was written by some 45-year-old guy who just wants to sell them something," he says. Instead, teens want to buy from corporations that remind them of themselves. Randomly sticking actors wearing nose rings in a chewing-gum ad won't do the trick, he warns. Instead, the best marketing efforts help companies look less like slick megacorporations and more like unpolished, offbeat underdogs, he says. When Loserkids' professionally designed Web site was first rolled out, Hoppus notes, it had the clean, well-organized layout of an Amazon.com -- the kiss of death as far as he and DeLonge were concerned. They quickly had the site retooled to create a less earnest look that now features, for example, hundreds of snapshots of fans. "That's our version of branding," says Hoppus.

The girls fly past Abercrombie & Fitch. I express surprise, pointing out to my daughter that when I went clothes shopping with her some months before, she had wanted to go only to Abercrombie & Fitch. But the three girls give a communal shrug. "Only rich kids go there now," says one, noting that equally stylish clothes are available at other stores at lower prices. I notice, in fact, that whereas the store used to encase throngs of teenagers, it now looks mostly empty.

Blink-182 rule #2: Teens are fickle. Deal with it.

When it comes to being hot with teens, it's a matter of living by the sword and dying by the sword, according to Hoppus. "Kids want to see the envelope being pushed," he says. "You can't predict the cycles, but you know they're going to change. Everyone wants something different from what they had before."

Hoppus notes that some skateboard and accessories companies remain novel with teenagers by continually inventing new "companies" -- that is, new logos and color schemes that make it seem as if the products were being brought out by small start-up businesses. "They just start from ground zero," he says.

The pace of change is even faster for Web sites aimed at teens. Loserkids changes as often as some news sites. "It has to evolve," says Hoppus. "If they log in and see the same thing as a month ago, forget it. But the trick is to keep it fresh without being overwhelming or losing the instant recognition of who you are."

It has also not escaped Hoppus's notice that hot bands have a way of suddenly becoming yesterday's news. "We always have that fear of becoming unexciting," he says.

At the mall, I ask my daughter's friends how they feel about shopping with their parents. Not surprisingly, they tell me they prefer to shop without them, even though they usually get to spend more than three times as much money with their mothers in tow than without them -- more than $100, on average, versus $30 when they're on their own. "My mother makes me try on things that are ugly or cheap," explains one.

Blink-182 rule #3: Listen.

Even though most of us tend to think of teens as being opaque, the truth is, they're pretty open about what they want, notes Hoppus. The problem is often simply that adults don't listen. When it comes to teenagers and their buying practices, most parents don't want to be treated like blank checks, of course, so they are obligated to offer guidance. But what excuse do businesses have for not paying attention to what teens are asking for? "Generation Y can get whatever it wants at the snap of a finger," says Hoppus. "You'd better be ready to give it to them."

Even Hoppus -- who after all hasn't been a teenager for almost a decade -- says he works hard to stay on top of teens' interests; he talks with fans before every concert. "You don't have to be at their level; you just have to understand where they are and respect it," he says.

Hoppus concedes that some people have been out of touch with teens for so long that they aren't going to be able to understand kids' needs no matter how much time they put into the effort. "The sad thing is, we all had expertise in relating to teens at one time, but we chose to grow up," he says. "I still consider myself a kid, and that's not true of most 28-year-olds." His advice to business owners who have lost that youthful state of mind: hire someone who hasn't.

The three girls finally find a store in the mall that they say they really like -- a clothing store called Express. They suddenly seem very sophisticated to me as with furrowed brows they compare notes on the relative merits of various tank-top-support mechanisms. I look around; the store has an edgy, almost ironically glamorous aura to it, with pink neon lighting snaking across the mirrored ceiling, blown-up photos of twentysomething models, and a long row of blue-jeaned mannequin legs spinning in midair. I ask the girls whom they think this store is targeted to. They confer and tell me with some certainty that it's aimed at professional women in their early twenties. I look around again; everyone in the busy store looks to be about 15 or so, except me, a few mothers accompanying their daughters, and the sales help, who all look to be about 18. And then it hits me: the store is designed to embody a 15-year-old's idea of what a 25-year-old's hip clothing store would look like.

Blink-182 rule #4: Adults really can influence teens.

Contrary to popular opinion, says DeLonge, teens don't despise the idea of growing up. In fact, he says, they can't wait to grow up and are quick to idolize people who are older than they are and who embody their own aspirations. "As a kid you're always looking for direction," he says. "You look up to people, and you want them to show you what's cool."

Teens' admiration for people who are ahead of them in life carries over into their behavior as consumers, according to DeLonge. "Everything they buy is associated with someone they think is cool," he says. DeLonge notes that he and Hoppus hired a snowboarder to run day-to-day operations at Loserkids, knowing that that would provide instant credibility to the site. "We didn't want some guy who would just look at sales charts," he says.

DeLonge concedes that even he and Hoppus aren't above imitating the lifestyle of older folks, noting that they have taken up golf. But he insists the line has to be drawn somewhere. "We won't wear golf clothes," he says. "I'm the only guy on the course with a T-shirt and tattoos."

I ask the girls to describe the ideal store.

"It depends on who you are," says one.

"OK," I persist, "what's the ideal store for who you are?"

"I don't know," she says, pausing a moment to reflect. "Who am I?"

Blink-182 rule #5: Think subculture.

Teenagers often seem like professional rebels. But DeLonge observes that even teens who are determined to stand out usually harbor an intense desire to blend in as well. "It's a weird circular thing," he explains. "On one hand you want to be different, but on the other you really want to fit in." The compromise that teens typically strike, he says, is to end up fitting into some community that offers homogeneity within the group but that allows them to stand out from teens in other groups. "Kids are constantly attaching themselves to some look or scene in an effort to search out their identity," says DeLonge.

He notes that businesses can discover large, lucrative niches by orienting themselves toward a particular teen lifestyle -- jocky, artsy, hip-hop, and so forth. DeLonge and Hoppus built Blink's core following, as well as Loserkids' customer base, around teen enthusiasts of board sports -- that is, skateboarding, snowboarding, and surfing. They did it because they themselves were skateboarders, but it has worked out to be a fortuitous focus: not only has the board-sport community grown into the millions, particularly with the explosion in the popularity of snowboarding, but the music and clothing associated with it have caught on with young people outside that community as well.

Hoppus points out with no small amount of disdain that some advertisers have tried to cash in on the board-sport craze by arbitrarily sprinkling skateboarders throughout their efforts -- and that skateboarders are all of a sudden appearing in a growing number of MTV rock videos. "Nobody's fooled by that," he says. (Personally, I'm pleased to hear that rock-video producers can be as lame as the rest of us.)

I ask the girls what they think of Filene's, a traditional department store at one end of the mall, and they tell me they go there occasionally "just to try on funny stuff you'd never buy." Later they take me to an accessories store called Claire's that's jammed with racks of brightly colored hair clips, plastic necklaces, and novelty pens; it reminds me of a candy store. I interrupt a slap-bracelet melee to ask the girls whom they think this store is targeted to. Twelve-year-olds, they tell me, before shrieking at the discovery of a shelf filled with miniature Slinkies. I look around; I see one girl who looks about 12, and eight girls who look 15.

Blink-182 rule #6: Lighten up.

Teenagers relate to humor, silliness, and irreverence more easily than to any other styles, says Hoppus. "Kids are trapped in school all day long, dealing with serious stuff," he explains. "They don't get as many laughs as grown-ups do."

In fact, DeLonge and Hoppus agree that a certain sharp-edged silliness in their own relationship is a cornerstone of Blink's success. "We don't take anything we do seriously," says DeLonge. Laughing at someone else's expense is particularly rewarding for teens, says Hoppus. "Most of us go through that stage with a lot of insecurity and self-doubt," he says, "and there's no question you feel better about yourself if you can cut someone else down in a funny way. Tom and I have made a career out of it."

Before we leave the mall, the girls afford their most enthusiastic thumbs-up of the evening to a hemp-bracelet kit. I found it in the Discovery Channel Store.

My rule: Never give up.

David H. Freedman is a contributor to Inc.

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