Visitors to Room 139 at Fairfax County's Hayfield Secondary School are in for a surprise if they think they are walking into just another classroom.

Room 139 is a fashion merchandising classroom -- and doubles as Jeffrey's Department Store. Jeffrey's is an attractively decorated boutique featuring men's and women's clothing and accessories. It is operated by students in Amelia M. Myers' course in fashion merchandising.

"There is only one Jeffrey's," said Myers, who last summer developed the idea of having students actually operate a retail store. By doing so, Myers' students learn how to organize a business and to select, display and sell merchandise.

The idea of teaching vocational skills in high school is hardly new. Distributive education classes specializing in vocational training allow students to work part-time while getting classroom instruction applicable to retail, wholesale and service careers.

"Most (distributive education) classes use simulation to teach the course," Myers said.

The concept of Jeffrey's Department Store originated as a retail simulation written by two college professors who give courses for distributive education teachers. The simulation takes students through the different phases of a retailing operation by having them fill in make-believe application forms, sales slips and inventory sheets. In the simulation, cards represent merchandise.

But Myers took the Jeffrey's simulation concept and adapted it to specialization in fashion merchandising. "Simulation is make-believe. I made it reality," Myers said.

Reality it is, for the store has already made sales exceeding $4,000 since its opening in late September.

The store is open every Tuesday and Thursday from 2 p.m. to 3:30 p.m. Some items, such as Kinney shoes and accessories, are kept in stock and may be bought directly from Jeffrey's for the regular Kinney retail price.

The clothing on display at Jeffrey's -- provided by the Queen's Way to Fashion Company -- are only samples of designs and sizes. Queen's Way to Fashion is a direct-sales company, and the clothes must be ordered from its catalogue.

In addition to selling at Jeffrey's, students also take the catalogue to customers' homes. Most sales are made to friends and neighbors who have seen the catalogue.

Just as sales clerks in many stores earn a commission, so does the Jeffrey's staff. The money will be used to pay for a field trip to New York to see the fashion industry in operation.

Eight senior girls make up the management team running Jeffrey's under Myers' guidance. To make sure all members of the team get varied experience, the girls rotate the responsibilities of choosing merchandise, arranging displays, keeping inventory and sales records, and scheduling sales clerks' hours.

The team even has a personnel manager who interviews applicants. "The students from my beginning fashion merchandising class fill out application forms and are interviewed by a member of the management team," Myers said.

"It doesn't matter if the girls going into fashion merchandising or not," Myers said. "The important thing is that they learn to deal with people. Human relations and communication are two valuable aspects they get out of this program."

Like many new stores, Jeffrey's is having some communications problems in trying to let customers know its existence. "Advertising is expensive, even in our own school paper," Myers said. An average of about 10 potential customers a week come into the store, Myers said.

To increase sales, Myers' students are planning to give several fashion shows. Some will be in homes, with eight to 10 people attending. Others will be held in the school cafeteria during lunch time.

Students are now learning to design advertisements to be placed in Springfield papers. They hope the ads will entice Christmas shoppers to Jeffrey's.