A mother tells why she's pleased with 'Ecole Bilingue'

Two years ago our family moved from Paris to Boston. I was going to be a full-time working mother for the first time. My husband and I were concerned first of all about finding an environment where our three- and six-year-olds would not feel too separated from the family atmosphere.

Second, we wanted them to have the same type of education we ourselves had received back in France, so that when we returned home in a few years the children would not be lost in the demanding French educational system.

We found our answer in nearby Cambridge: the Ecole Bilingue. This school was founded in 1962 by several French mothers, and has been receiving grants from the French government. It has maintained itself courageously at times, and in the past few years has won its place among other private schools in the community, in part because of an energetic new management.

My first visit to the school didn't impress me much. For one thing, I'd never seen a school in a basement before (it is currently renting a church basement), and as my visit was after school hours, this emptiness - with books and only inanimate signs of childrens' presence - was not too cheery. However, I was warmly greeted in French, and learned that the French consulate in Boston granted scholarships to help toward French pupils' tuition.

My husband and I decided this was the closest to a home atmosphere we could offer our precious ones.

Once they got used to lunch boxes, and to not always waiting for orders, their adaptation was remarkably smooth and painless. I think the day I really fell in love with the school was a couple of months later when I attended its Thanksgiving celebration.

There was so much spontaneity and imagination in the performance! I felt grateful that our children were learning enthusiastically to appreciate a new culture while not forgetting or even wishing to forget their own.

Our youngest one, singing with all her heart, ''The pumpkin ran away . . . , '' was then in the nursery class, a class that carries essentially the activities of a French Maternelle.

At this level, mostly French is spoken so as to immerse the American children in the foreign language that they do not hear anywhere else. The French-speaking ones catch on to English anyway - they have one big incentive: TV speaks English.

''The way children adapt to new environments will always be amazing,'' I thought, watching our older one, dressed as a Pilgrim, saying his short line with a perfect accent. And I recalled the years, as an English teacher in France , that I had tried to coach my high school students to even approach a correct pronunciation.

(I have to confess that now my children's pronunciation is much more genuine than mine!)

The modest size of the school, and its small classes - the latter a necessary aspect for adapting the teaching to the various levels of linguistic understanding of the pupils - encourages a family atmosphere. We also found an active and warm PTA, and dedicated teachers, all firm believers in bilingual education, of course.

Here is how bilingualism works at Ecole Bilingue: In the morning the classes are conducted in English by American teachers, in French in the afternoon by French institutrices.

The originality of the school lies here: Both curriculums are carried out simultaneously, the American teachers teaching the American program and the French institutrices the French one.

Because both curriculums cannot be covered exhaustively, a few choices have to be made. For instance, instead of ''Nos ancetres les Gaulois'' (''Our ancestors the Celts''), the traditional opening of all French history books, our third-grader learns something like ''Our ancestors the Indians.'' Neither reflects the exact truth anyway, and the Indian image is certainly more appealing to an eight-year-old than the Celtic!

But basically, he has learned to read and write just as we did - is battling with the grammaire the way we used to - brings home some good French schoolbooks for his homework, and has learned fables by Jean de La Fontaine as well as poems of a few modern writers.

His young sister is concentrating very hard on writing, in cursives, ''Le chat de Beatrice est petit.''

It appears from the good results on the United States national tests that have been taken by all the students, and from the smooth assimilation of French pupils back to their educational system, that a major part of each curriculum (French as well as English) is accomplished successfully.

The results of this unusual educational experience are quite encouraging and appeal to many parents who have no particular knowledge of French: Their children speak both languages fluently, and can read and write them at the normal age. And they recite and sing them! Thinking of what this school means to us, we find our two primary concerns have been largely satisfied, but there is more.

We appreciate the openness and international spirit prevalent in the school. The children come from very diverse cultural and social backgrounds - business, art, science, diplomatic - and from many countries.

Americans constitute roughly 50 percent of the enrollment, the other children coming from various countries in Europe, the Middle East, Africa, South America, Asia. All these cultures blend harmoniously in the little world of the school. And all the children seem very much aware of the privilege that is theirs to speak more than one language, and also to be different, each one bringing something to the school community.

In the end this may be the aspect we shall appreciate most about the school, for we share with the other parents and teachers the belief that bilingual children will eventually turn into more tolerant people.