At age 3 1/2 she knew just what she wanted to be - a dancer

When our daughter was 31/ 2 and saw her first ''Nutcracker,'' she knew she wanted to take dancing lessons. When she was 5 and learned she would be eligible to study at the Boston Ballet in another year, she asked us to sign her up. And now, at the age of 10, she is studying ballet Monday through Saturday, and often on Sundays when one of the companies she performs with (the Boston or New England Ballets) is in rehearsal.

How to accommodate such a schedule and still keep a sense of balance and perspective for Nicole, not to mention the rest of the family, is a question my husband and I have been wrestling with for several years now.

An obvious solution has been to give our daughter as intensive an education as she can assimilate at a young age, so that if college must be deferred - as would be the case if she pursued ballet professionally - she would at least possess the academic skills to function ably without a bachelor's or advanced degree.

Since Boston lacks a true school of the performing arts, on the order of New York City's, we decided to seek out a school that would emphasize academics and not place undue emphasis on extracurricular activities. Private school seemed an obvious route to explore, partly because of the smaller classes and custom-tailored curriculum that could more readily accommodate a complicated schedule, not to mention a complicated child.

Another consideration, for us, was finances. We were fortunate enough to read about the Chestnut Hill School, in Chestnut Hill, Mass., which gives an annual partial scholarship to a child talented in the arts. Nicole tried out, won, and began her private school education as of fourth grade.

In addition to small classes, more individual attention, and mobility between grades, private school has provided a teaching corps that recognizes the importance of dealing with the total person - in Nicole's case, as Yeats would say, it's impossible to separate ''the dancer from the dance.''

What else is different about raising a child single-mindedly committed to a dominant passion? My husband and I feel it's imperative to keep everything in perspective. We worry that, no matter how hard we try, she might, at age 21, look back and say: ''What happened to my childhood?''

As an example: Nicole is a gifted skier and thrives on the exhilaration of downhill runs. We've so far refrained from recommending she stop, although skiing and dance - as her dance teachers are wont to point out - are antithetical: everything that turns out in dance turns in in skiing.

As far as possible, in other words, we have gone out of our way to see that her childhood remains as normal as can be - normal, in this case, being defined as dancing two school nights a week until 9 o'clock and spending most of her weekends in a rehearsal studio. But Nicole remains as much a part of the pre-adolescent social mainstream as we can possibly manage.

Parental direction and guidance have also helped Nicole put the chunks of available time she does have (35-minute drives to dance studios; hour-long breaks between her ballet and pointe classes at Boston Ballet) to good use. Fortunately, she has always been a voracious reader, consuming between three to four books a week. By guiding her reading selections toward works by C. S. Lewis or Lloyd Alexander, we've encouraged her to fill her ''spare'' time more meaningfully.

Obviously every child has dreams. Be they modest or grandiose, these dreams stimulate creative growth and frequently nurture success. It is a parent's job to give positive direction to these dreams. As one mother said, commenting on her 18-year-old son who left American Ballet Theatre II in New York City to return home and enroll at Northeastern University: ''You have to have something to fall back on if your feet no longer work.''

What Nicole will have available to fall back on, when and if needed, are a strong and nurturing family support system (a worshipful four-year-old sister and a brother whose prowess as a chess player has made him a celebrity in his own right), a strong educational foundation, and a view of life that validates the worth of pursuing a dream passionately but keeping options open, should the awakening occur outside the ''Palace of Sweets'' where Clara wakes up in the second act of ''The Nutcracker.''

Nicole was, in fact, Clara in the 1983 Boston Ballet production of ''The Nutcracker,'' and so far her dance life has been touched with marzipan shepherdesses and polichinelles. But we want her to know that beauty and creativity exist in many forms outside dance - poetry, a mathematical construct, a moving photo essay. For her formative years, our aim is that her mind improve commensurately with her dance technique so that whatever she becomes represents the best possible Nicole Elizabeth Eldridge.

Beyond the heights of dancing Sugar Plum Fairy or winning an Olympic gold medal for swimming or gymnastics or the like, isn't that really every parent's dream?