Mayor Rudolph Giuliani's task force on bilingual education is right to insist that every parent be given full information and be allowed to reject enrollment in the program. In addition, the task force wants the board to expand English exposure for children in bilingual education. But the most important problem is the chronic shortage of bilingual teachers, too many of whom are uncertified. In the absence of skilled teachers, everything else is just tinkering at the margins.

Over the last decade and a half, New York City has developed several programs to teach every academic subject in a range of foreign languages. The overall bilingual program now enrolls about 176,000 students. Contrary to popular belief, all of these children receive at least some course instruction in English. Half of the bilingual students are enrolled in the English-as-a-second-language program, in which classes are taught in English and the children are taught English as well in special language classes. For the other half of the bilingual students, the regular curriculum is taught mainly in their native languages.

Many critics of the system are touting a radical program in which students would receive all instruction in English only. But the truth is that many children already get instruction that comes close to "immersion," except that it allows teachers to provide occasional help in a child's native language.

The latest push for radical changes emanates from California, which two years ago passed a referendum requiring that instruction be overwhelmingly in English. Supporters have declared it a success, based on tests that show scores rising for all children across the state. But the scores are attributable to many things, including smaller class size, a more rigorous curriculum and a state program that pays schools a bonus for higher scores. Also, some scholars say a math-score gap between native and non-native speakers has widened, suggesting that the new system may yet yield damage.

New York City's bilingual system has a less than stellar record. Only 62 percent of children who enter the system in kindergarten leave the bilingual program within three years, and that number falls to 11 percent for those who enter in ninth grade. The youngest children are easier to teach because they learn language quickly and do not need to master complicated content. The older children are also burdened by a lack of qualified teachers. By junior high school, nearly one in three bilingual teachers is uncertified about twice the rate for traditional teachers. Imagine being a foreign-born child struggling to learn English from a teacher who does not speak it fluently.

Mayor Giuliani's task force was right to highlight the problems and insist that the Board of Education take a critical look at the program. Schools Chancellor Harold Levy must ensure that children are no longer forced into the system and that those who now receive a great deal of their instruction in a foreign language are given greater exposure to English. But New York's bilingual learners will continue to founder unless the city and state embark on a vigorous effort to attract, recruit and retain talented new teachers.