Imagine that you are new to this country. You've learned enough English to buy groceries, do your banking, understand rudimentary instructions from your boss. You can get by just fine.

Until your children start school.

Now imagine trying to understand: The PTA meets on the second Tuesday of every month. Virginia Literacy Passport Test. Parent-teacher conference. Geometry. Field trip. Magnet program. CD-ROM. Disk drive.

The parlance of the U.S. school system is confusing enough for American parents. But for the growing number of non-English-speaking immigrants, it can be incomprehensible. One in six residents in the Washington area is foreign-born, and officials say that an increasing number are arriving in this country with weak or no English skills.

The challenge for schools is not only to teach the children but also to help their parents understand the perplexing customs and language that permeate American schools, because, research shows, if parents are bewildered and intimidated by the education system, then their children have a far greater likelihood of dropping out or performing poorly.

Schools like Sleepy Hollow Elementary in Fairfax County are on the frontier in this regard. Largely because Sleepy Hollow's boundary lines were redrawn in 1997, the English as a Second Language enrollment at the school near Seven Corners has almost doubled in the past three years to 117 students, most of them the sons and daughters of Hispanic and Vietnamese immigrants. Meanwhile, it is difficult for these parents -- who typically have young children and work long hours as hotel housekeepers, cabdrivers, waiters and waitresses -- to improve their own English skills. The large ESL classes offered by local governments are impractical because they meet several evenings a week, take several months to complete and have long waiting lists.

Knowing this, ESL teachers Maggie Rosen and Karen DeMattos last December obtained funding from the county to start a family literacy night at Sleepy Hollow. It's a program that provides English classes, computer instruction and child care all at once one evening a week. Seven Fairfax County schools now offer family literacy night, and "everybody wants one," says Elaine Baush, the county's coordinator of adult ESL programs.

One evening, while volunteers are helping the children with their homework in one room, technology aide Susan Carlson is working with the beginning-English parents in the computer lab, and county ESL instructor Diane Prosack is working in a room down the hall with parents who understand slightly more English. The parents' classes switch places after 45 minutes.

A short lesson once a week isn't going to make anyone fluent in English, says Prosack. But that's not the goal. The objective is to teach words like "backpack," "scissors," "pencil sharpener"; the days of the week; how to call in when a child is sick; how to tell someone what time your child leaves for school and returns home.

This evening, Prosack is helping her class identify pictures of a car, a bus, a taxi -- methods by which children may be arriving at school. "Isabelle," says Prosack to Isa-belle Garcia, 29, an at-home mom with three children whose husband works as a waiter. Prosack's voice is slow and deliberate. "How does your son get to school?"

Squinting and pursing her lips, Garcia struggles to find the words.

"He work to school," she says at last. "He walk to school."

Over the winter, the ritual of snow days, a burden to Washingtonians in any language, mystified the class. Teachers and other parents who serve as volunteer child-care providers while the ESL parents are in class printed out such phrases as "closed," "delayed two hours," "late opening." They even called in a couple of Vietnamese school custodians to help out, and eventually everyone understood the crucial directives.

The county doesn't have a concrete formula for assessing the program, but Rosen sees anecdotal evidence that it's succeeding: Participants now regularly volunteer in their children's classrooms. They attend new Spanish-speaking PTA meetings. A recent Fiesta Night party, put together by Spanish-speaking parents, attracted a healthy crowd.

And the experience of Vilma Herrera, the star pupil of family literacy night, is promising. A nurse's assistant who came to the United States from El Salvador in 1980, she got by with a smattering of English for years. But now her children's schoolwork is getting more complicated. Her daughter is 12, and her son is 9.

"Their homework is too hard," says Herrera, 40. "They say, `Oh, Mom, I need help,' and I can't." Encouraged by her progress at Sleepy Hollow, Herrera recently signed up for a larger county ESL class, which she'll start shortly.

"I want to learn English," she says. "I want my kids to become something."

Jacqueline L. Salmon covers family life for The Post.