"I like the trailer," fourth grader Roberto Santiago said of his classroom, which sits 15 feet removed from the rest of Lake Ridge Elementary School. "You don't have to hear the noisy third graders inside the school."

"Sometimes you get the feeling you're in the little old schoolhouse," said teacher Chris Schwarz, surveying a science class wedged into his 14-by-54-foot temporary classroom. "I spend half the day reputting things on the bulletin board because the space is narrow and kids are always brushing up against it accidentally."

About 2,700 Prince William County pupils attend class in trailers. Most of those interviewed found them acceptable, but teachers gave them mixed reviews, and many parents view them with hostility.

School officials, meanwhile, are preparing to buy more.

Trailer classrooms apparently have come to stay in Prince William's school yards, a symbol of unbridled population growth outstripping the ability of the county to pay for needed facilities and services.

There are 100 "auxiliary classrooms" -- 64 trailers and 36 older modular units -- parked on school blacktops, the equivalent of three elementary schools for this 39,100-student system.

Thirty-five of the auxiliary classrooms are new this year, and Superintendent Edward L. Kelly proposes installing 26 more next year at a cost of $420,000.

While trailers and other movable classrooms are not new as a means of dealing with growth in suburban areas, Prince William has proportionately more than do other localities near Washington.

In Fairfax County, 219 movable classrooms serve the 130,000-student system, while across the Potomac River in Montgomery County, where the school population is fast approaching 100,000, there are 188 auxiliary classrooms, many of them new modular units. Prince George's County has 177 and a student population of 103,500.

Being in a trailer classroom is a little like going to school in a hallway. Teachers usually arrange desks in a couple of rows in the middle of the long, narrow space. Children at each end are left to crane their necks for a decent view of the blackboard.

But with the usual adaptability of children, fourth and fifth graders at Lake Ridge Elementary, which has five trailers and two other "relocatables," take this in stride.

Nor do they seem very concerned about having to brave the elements when they change classes or go for lunch, library time or special classes in the main school building.

It is not unusual to see pupils heading out the trailer door jacketless on a cold winter day.

Fourth grade teacher Carolyn Cornwell said she likes the "coziness" of the trailer and "enjoys being out here." Her colleague, Yvonne Bond, a fifth grade teacher, was not so enthusiastic.

"For one thing, fifth graders tend to get large by the end of the year, "Sometimes you get the feeling you're in the little old schoolhouse."

-- teacher Chris Schwarz

and it's crowded," she said. "There's also no running water, so if I want to clean the boards, we have to send someone into the school to get water."

Whether they find the trailers cozy or claustrophobic, most teachers complain about the lack of storage space.

"We teachers try to share ideas on how to cope," said Cornwell, who has lined up laundry baskets under a work table as repositories for book bags and lunches.

Coat closets are never big enough, and most children keep their jackets slung on the backs of their seats.

Board space is also limited, so teachers hang charts and homework assignments on the walls.

The trailers are least popular with parents.

"Everyone wishes they weren't there," said Susan Olesak, president of the Lake Ridge Parent Teacher Organization. "But most people prefer them to busing their children elsewhere."

School Board Vice Chairman Maureen Caddigan (Dumfries) says she gets plenty of calls from parents complaining about the trailers at their children's schools.

"They would be more understanding if they thought they were temporary," Caddigan said. "But Dumfries {Elementary School} has had some for 20 years."

When Kelly met with parents and community leaders in fall to establish priorities for the school system's six-year capital improvements plan, getting rid of all the trailers was at the top of everyone's list.

However, school officials calculated that it would require a $130 million construction program over the next six years, which many say is beyond Prince William's means, if other county capital improvement projects are to be financed as well.

So for the foreseeable future, trailers will remain.

One of their advantages, according to Steve Snarr, director of school plant maintenance, is their mobility.

If school construction catches up with population growth in the eastern part of the county, and the west begins to boom, the trailers can simply be hitched to tractor trucks and follow the children -- a kind of "wagon train west," school officials are fond of saying.