New York ? The first hint of fall is here: Back-to-school clothes are filling retailers’ racks.

But the shoppers eagerly awaiting the corduroy and cardigans are not necessarily the same people who will be filling classrooms. In fact, many of them haven’t fit into their “school clothes” in several years.

By keeping this entire outfit fitted, back-to-school pieces such as a corduroy jacket and jeans look more adult.

“No matter how old you are, when it’s fall you think at the very least ‘I need new school shoes or boots this year,”‘ says Shari Hershon, senior vice president of design for Ann Taylor Loft.

Caren Bell, spokeswoman for Tommy Jeans, a division of Tommy Hilfiger, says back-to-school clothes offer both a physical and emotional comfort thanks to the easiness of the pieces.

“You feel good because it brings you back to a happy memory and you can be fashion-forward in clothes that really are comfortable,” she says.

The back-to-school look that most people gravitate toward is classic yet casual, and, of course, seasonal. But the pieces are dictated more by a mood than fashion trends, which makes it easy for the styles to be adapted for adults who have a teen spirit but not the lifestyle to go along with it.

Depending on how they’re worn, rugby shirts, kilt skirts and plaid or houndstooth patterns can look like either school uniforms or country-club chic.

Back-to-school styles often are an edgier take on traditional preppy looks, observes Bell. “Preppy styles work for any age that’s why they’re so classic.”

She points to the rugby shirt. For a young hipster, the rugby might be a bias cut with pocket or patch details and paired with tint-wash jeans; when a grown-up puts on a rugby shirt, it might be worn under a sweater, or with chinos or a denim jacket.

But Bell says an adult can remain fashion-forward by incorporating new details into otherwise classic garments, such as boot-cut legs on khaki twill pants.

Navy, according to Bell, is the best color to transcend the ages.

Meanwhile, Hershon notes that the rich crimsons, camels and browns that are popular for fall 2002 also evoke a back-to-school feel.

Proportion is key when adults choose clothes that have a back-to-school look.

Classic men’s dress shirts with a ruffle or pleat can give a sophisticated and crisp touch to an otherwise collegiate outfit for a woman in her 20s and up, Hershon suggests, and a novelty plaid or graphic print updates a look she might have already worn years ago.

A pleated or kilt skirt can look more age-appropriate if the skirt is a little longer, made in a textured fabric and paired with boots instead of flats, she adds.

“It’s not as much about the pieces as how they’re combined and how they’re accessorized,” Hershon says.

Once the weather does turn chillier, try a “contemporary-but-not-too-young” duster twin set instead of a traditional cardigan for a longer, leaner silhouette a shape most women past their teen-age years want, says Laura McDowell, fashion spokeswoman for TJ Maxx.

Also, she suggests, choose jeans that are narrow through the hip and leg.

The more adult versions of this season’s popular jean jacket are a denim wrap or a three-quarter length jacket in twill.

“Take the trend and find it in the more adult look,” McDowell advises.

One garment that fits any age literally and figuratively is the hooded sweatshirt. It can be worn by kids, juniors and adults. Just make sure the cut and color work for you, McDowell says.