Playwright Wendy Wasserstein has become a spokeswoman for a particular kind of female: those who graduated from college in the late '60s and early '70s, competent yet befuddled about their goals, always within five or 10 pounds of their ideal weight, feminists who want marriage and babies but find that the sexual revolution has made it harder to have them.

"Isn't It Romantic," which opened last week at Arena Stage's Kreeger Theater and is still playing off-Broadway, focuses on two such women, and her earlier "Uncommon Women and Others" had a whole cast of them, at and after a women's college.

A graduate of Mount Holyoke and Yale Drama School, Wasserstein is not unlike any of her characters, especially the funny ones who say that self-discipline is beyond their reach. Ask her, for example, about her writing schedule.

"I wish I could say I get up at 5, jogged, wrote for four hours, had a delicious salad, spent quality time with my kid she doesn't have one and made a fabulous quiche," she says. "But I don't. I'm compulsive. I might write for two months, night and day."

And when she's not writing compulsively?

"I think. I have lunch with former Yale classmate Chris Durang if he's available. His next play is opening soon, so we'll be able to have lunch again. And there are periods when you are just reading reviews of other people's plays. That's a lot of fun," she deadpans.

She also teaches at Columbia, judges the occasional contest and sits on the occasional panel, and is an excellent shopper. "Not for myself. I buy good presents. I love thinking up exactly what I want to give someone, and then figuring out the best place to get it."

She is, as any viewer of "Isn't It Romantic" would guess, a born and bred New Yorker, a product of the Upper West Side. Her high school was not one of the progressive, liberal ones ("Marion Javits went to my high school -- that's all you need to know"), and she spent many years going to the June Taylor dance studio.

"My mother would pick me up from dancing school on Saturday and take me to lunch at some place like Schrafft's, and then we'd go to a matinee. I saw things like 'Mr. President' and 'All American' with Ray Bolger. Kids can't grow up like that anymore -- the tickets cost too much."

After college, Wasserstein applied to both Columbia Business School and Yale Drama School. She got into both. Thanks to having taken Israel Horowitz's playwriting workshop, she had the experience of a staged reading of her first work, "Any Woman Can't."

She has begun to make her living as a playwright, helped by a few unproduced screenplays, some television and grants. Her most recent work, a musical about a family going to Miami Beach in the 1950s, was written on commission for Playwrights' Horizons for $4,000. It took her several years ("Isn't It Romantic" went through seven drafts) and will be produced next year. A few years ago she received a Guggenheim grant.

"My father asked me what that was, and I said it was a grant to artists so they could finish their work.

"He said, 'No daughter of mine is going on welfare!' "

Wasserstein has no pretentions to being profound. "I think it was Woody Allen who said, 'If you write comedy you sit at the children's table.' And there's part of you that wants to sit at the grown-ups' table, even though you know the food is better at the children's table. But I am not trying to write didactic theater. It's not about two girls in lumber jackets on a tractor . . . I want to do it subtly."

The genesis of "Isn't It Romantic" came a few years ago when Wasserstein learned that an old friend who had preached independence was getting married on the verge of her 30th birthday. Suddenly she began hearing of other age-30 altar marches, and baby showers blossomed like chicken pox. "Biological time bombs were going off all over Manhattan," she says. "It was like, it's not wild and passionate, but it's time."

She is not immune to such pressures herself but retains the notion, like Janie Blumberg in "Isn't It Romantic," that marriage should come with true romance. And in case you're wondering, being a successful playwright is not necessarily a great way to meet interesting men, she says. Quote of the Week

"Acting is a disgusting profession. It abounds in dependency . . . It's a fluke when an experience in the theater becomes profitable for actors," said the noted German actor Ekkehard Schall, interviewed in American Theatre magazine.

"Godspell" will carry on at Ford's Theatre through July 28, with a hiatus between May 27 and June 5 . . . "Last Days at the Dixie Girl Cafe" will play thrugh June 2 at Horizons . . . Coming Events

Tom Stoppard's "The Real Thing" opens at the National May 21, starring Brian Bedford and Sara Botsford . . . Mary Woods will perform a one-woman piece about Katherine Cornell at the National Portrait Gallery, May 10 through 12. Call 357-2920 . . . "The Knight from Olmedo," by Lope de Vega, opens Thursday at the GALA Theatre. Call 626-2831 . . . End Notes

Zelda Fichandler has received an award in New York by the Double Image Theatre, honoring her work in recognizing "the expanding need for cooperation between the arts and the private sector" . . . Source Theatre is looking for productions for its fifth theater festival, which runs from July 8 to 28. Call Keith Parker at 462-1073.