Smithsonian curators are stalking some exotic species of American wildlife - the shaggy, black-breasted "Headbanger," the plain-tufted "Nerd," the lavishly plumed "Preppy" - for future scholars to puzzle over.

These remarkable birds are America's teenagers, whose strange and sometimes bizarre clothing styles are being documented by fellow high school students at the request of researchers at the National Museum of American History.Claudia Kidwell, the museum's curator of costumes, believes this first nationwide survey of adolescent fashion tastes will yield important clues about the teenage subculture of the 1990s.

What scholars of the 21st century will think, heaven only knows. Don't bother asking today's parents, who may have forgotten how their Age of Aquarius peace beads and miniskirts shocked an older generation.

Now, they're similarly baffled when 15-year-old sons suddenly rip holes in the knees of their designer jeans, shave their heads, wear earrings and clomp around in enormous athletic shoes with laces left inexplicably untied.

These sartorial mysteries intrigue Kidwell, who is convinced that people's clothing historically tells much about their daily lives, their cultural values, gender roles, hopes and fears.

"Driven to the wall, the one thing that's really important for teenagers is that they have control over their appearance and express their individuality," she said. "For a teenager to decide what they are going to wear the next morning is a very complex issue."

They may be rebelling against the rules of parents and school authorities, or dressing to conform with their closest friends.

"Either way, the same thing is going on," said Kidwell, who has two daughters. In the crucial task of developing their own identity, she said, "clothing is the one thing kids can control more easily than other parts of their lives."

To find out what teenagers around the country are wearing - and why - Kidwell and museum associate Michelle Smith produced a school activity kit with a grant from Brother International Corp., and offered it to 16,000 high school teachers for free. About 6,000 teachers responded.

Early returns from teenage bird watchers reported sightings of "Preps," "Hoods," "Farmers," "Normal," "Jocks" and "Nerds" in high school classrooms in Ohio.

From Kentucky came detailed observations on "Headbangers" and "Casuals." In South Carolina, there are "Hype" and "Ruffian" clothing styles.

An Ohio correspondent said the Normal look requires "faded or acid-washed, French rolled jeans" and T-shirts or sweatshirts, with "hair scrunchies" among the accessories. It's cheap and comfortable, she wrote, and "makes it easy to blend and fit in with crowds."

Preps favor expensive, brand-name clothing. "Preppy people are always perfect, with even matching fingernail polish," she wrote. "A preppy guy does not have facial hair."

"Hoods" in Ohio apparently resemble Kentucky's "Headbangers" and South Carolina's "Ruffians." They like long hair, dangling earrings and lots of leather. Their black T-shirts feature artwork from heavy metal rock bands.

"Disgusting, less than eloquent, distasteful," wrote one South Carolina girl.

Similar disdain was expressed in Ohio for the Nerd style, which includes thick glasses, neatly parted hair, short-sleeved shirt, digital watch, pocket calculator and non-brand denims with "high-water cuffs."

Black teens and some whites in South Carolina classrooms prefer the "Hype" look, with baggy trousers, loose, brightly colored jackets and gold chains that seem inspired by hipster Spike Lee Jones. There's nostalgia in the "Avant Garde" style, which features "unordinary earrings, peace beads, braided belts, Jesus sandals."

Already, Kidwell says the survey has confirmed her suspicions that many teenagers are inspired by national clothing chains, fashion magazines, music video stars and each other.

But in this era of mass merchandising, she wonders why faddish styles differ within the same school and from one region to another.