Things are looking up for taller women. They are less self-conscious, and more breezily athletic, self-assured, and graceful in the way they handle their height. They are getting far better attention from fashion sources.

Tall women stand tall and walk tall, and the slouch and stoop of the past is noticeably less, particularly in the younger generation of women.

Talls also are getting more interesting press. The social columns are full of photographs of shorter men with beautiful taller women on their arms. As one tall girl points out, "This whole Diane Keaton-Woody Allen syndrome makes the small man-tall woman romantic combination suddenly seem far more in the mode."

How tall is tall? Statistics show that 90 percent of all women are between 4 feet 11 1/2 inches tall and 5 feet 7 1/2 inches tall. About 10 percent of the female population in the United States is over 5 feet 7 inches. Some people think all females are getting taller, but the average height for women from 18 to 24 is still about 5 feet 4 inches, according to the National Bureau of Standards. About 36 percent of women are taller than the average, and at least 5 percent grow into the 5 feet 9 inches to over 6 feet height category. California has more tall women than any other state and has sprouted several "extra tall women's clubs."

At one New York fashion model agency, Ford models Inc., leading models now range from 5 feet 7 inches up to 5 feet 9 1/2 inches, with 5 feet 8 1/2 inches as the average. There are no very thin "Twiggy" types among them. The emaciated look is out. The softly rounded, more womanly look is in.

As for fashion, one attractive blond executive in New York who is 5 feet 7 1 2 inches, says "I make all my own clothes in order to get the kind of fashion look I want."

Janet, who is in her 20s and is a nurse for children, is a statuesque 6 feet 1 inch. She loves being tall, except when she is at stand-up parties and has to stoop to catch the conversations. She has never minded dating shorter men because "they know how tall I am, and if they ask me out I figure it's because I am their preference." Like many of her tall friends, Janet goes to men's and boy's departments in stores and shops to find turtlenecks, slacks, jackets, and T-shirts, which are better quality and less in price than women's clothes.

Other sports-minded talls indicate they sometimes shop army and navy stores for down jackets, jeans, boots, and camping gear at discounted prices. At the other end of the fashion spectrum, Janet buys a very good designer dress whenever she can afford it in order to get a longer, more ample cut which she is slim enough to make fit.

"I've found that if you are taller and larger than most people you have to demand better quality," Janet says. "Cheap, sleazy stuff looks skimpy and awful. I find I have to buy better quality in everything, including furniture and cars."

Letitia, an etiquette specialist, is also 6 feet 1 inch, and she can afford high fashion. But she can almost never find it in good ready-to-wear. Sometimes she persuades a Seventh Avenue manufacturer to cut a few taller size garments especially for her, but they are costly. Usually, she has things made or orders clothes custom-tailored from Hong Kong.

"Beautiful, quality fabrics mean everthing to me, and I usually can't find them at the tall-girl shops where I shop for practical things like slacks, raincoats, gowns, and underwear," Letitia says.

Tall women, she observes, fare much better in these days of disco when they can dance solo.

"I grew up in cheek-to-cheek dancing days and was always running to the powder room to wipe the boys' hair oil off my chin. I hated it."

Geraldine, a real-estate saleswoman, is 5 feet 11 inches and agrees with Letitia that shopping for clothes is an agonizing process that requires far too much time. She says, "I search the racks in good stores like Saks and Bergdorf's and occasionally find something I can wear if I let out hems to the hilt. In desperation I go to the tall-girl shops, but I can afford better.

"I think a real fashion vacuum exists for taller, larger women who want really top quality clothes but can rarely find them."

Liz is 5 feet 9 inches, the same height as her husband, and she says she wears low heels when they are out together, despite her visions of Woody Allen, et al. But Liz, who is a magazine writer, wears high heels when she is alone.

She says she hated having to play boys' parts in plays at children's camp and always being asked to stand on the back row of group photographs. But now Liz enjoys her tall stature and being able to reach things on the top shelf of her etagere. She buys some European clothes, which are cut longer, and European pants, because they come uncuffed, she says, and she can turn them up herself.

For women who are looking for tall fashions at moderate prices, the picture is vastly improving and looking better every season. Lane Bryant, with its 193 stores around the country, now emphasizes its "tall and terrific" departments for the woman who is 5 feet 9 inches or over and gives far more attention to current sytles and properly proportioned hemlines, sleeves, and waist lengths. This chain also features tall fashions by such well-known designers as Gloria Vanderbilt, Diane Von Furstenberg, Levi strauss (jeans), Izod, Sasson, and Brittania. Suits for tall women here sell for $110 to $180, dresses from $50 to

Joy Pelz, manager of Lane Bryant's tall division, says, "Tall girls these days are proud of their height and want to capitalize on their natural ability to wear clothes beautifully. We are trying to help them."

Noreen Littman, buyer for the 65 Shelly's Tall Girl shops located in 15 states and headquartered in Los Angeles, agrees that tall women have been more insistent on up-to-the-minute styles, which this season has meant high heels, the suit look, tailored jackets, classic blazers, pleated skirts, pretty dresses , and well-cut jeans.

Mrs. Pelz and Mrs. Littman agree with Tall Specialties Inc., a New York buying office which specializes in tall fashions alone, that the tall markets is opening up and gaining new recognition, and that more and more manufacturers and designers are now eyeing the range with new interest.