It's been five years since the Shortnacy family of Fairfax has lived what most would call a normal family life. Since 1971, Gail and Frank Shortnacy have been providing a home for juvenile boys, and, at last count, they have had 85 boys join their family for as short a time as a month to nearly two years.

Now the Shortnacys and their three children, Scott, 17, Bruce, 14, and Cathy, 10, are moving into a new home to Manassas in July to "start being a small family again."

But the anticipation of being a family of five, as opposed to a family of 11, or nine, or seven, as they have been in the past at different times, is already mixed with a sense of loneliness, said Mrs. Shortnacy.

As a family, we did most of our growing with these boys," she said. "It was a terrific experience. "We've also apprehensive of the loneliness."

The Shortnacys, who live at 7117 Braddock Rd. in North Springfield, are one of four Fairfax families participating in a program developed by Fairfax County Juvenile and Domestic Relations District Court that places tennagers under the jurisdiction of the courts in foster homes for limited periods of time.

Most of the teen-agers have been by the courts for "status oftenses," said Camilla Stroud, coordinator of the juvenile courts group home program. Status offenses include running away from home, truancy and incorrigibility - where parents have lost control of their children. Sometimes a group home provides "the last chance for kids of make good before they really find themselves in trouble with the law," Stroud said.

"The major reason these kids go to a group home is to remove the child from his parents," she continued. "Most often communication has broken down between the child and the parents. It doesn't always mean the parents are bad parents. It's just that neither the parents or the kids are doing each other an good."

With the departure of the Shortnacys and another set of houseparents in the program, Mary and Richard Remley of Fairfax City, Stroud is looking for two new families to take their place. One would manage a long-term home for boys and another for girls.

The program started in the summer of 1975 with an $77,000 grant. The current $87,000 grant pays houseparents an annual salary of $9,000, a portion of rent and utilities, all daily food and clothing expenses for the youngsters and a $5 weekly allowance.

"What we need are couples who like teen-agers and find something rewarding in working with them," Stroud explained. "The only essential requirements are that the couples have solid, mature relationships themselves, that they have clearly established values and that they are not afraid of wielding authority."

The Shortnacys started taking in youths on a volunteer basis through a Springfield church they attended. In 1975 they joined the court's program on a formal basis.

"Years ago we had all different sorts of kids, most of them rougher than the kids we have now," Mrs. Shortnacy said. "For me, the tougher kids were easier to handle. They're more misdirected than anything else. Once you get their energies channeled in a worthwhile direction, they tend to be action people and leaders.

The stout, 36-year-old housemother, a native of New Jersey, described her husband Frank, an installer for the C and P Telephone Company, as quiet and softspoken, "my opposite."

"We handle the kids differently. The boys greatly respect Frank, and they understand where I stand," she said. "The boys tend to gravitate toward the parent, who best relates to them. In this family, they have a wide choice."

The Shortnacys have had several runaways from their Braddock Road log cabin home, but Mrs. Shortnacy says such insidents "are almost to be expected.

"They're just testing you out, finding out how much you care about them and what your expectations are. The runaways are returned to us if they run away only once. From then on it's smoother sailing."

She said some of the runaways have been apprehended by police for offenses while away from the Shortnacy home, but that no serious problems have occured in their home. None of the boys have ever distrubed the Shortnacy's neighbors, she said.

The most difficult aspect of providing a home for juveniles is "the effort you have to make to be on your toes all the time," Mrs. Shortnacy said. "You have to be one step ahead of teenagers, and you have to be calm. I have found you get more when you set your expectations high."

The most rewarding feature of being a houseparent "is seeing a kid finally get excited about himself, about life," she said.

"You see them come in at odds with themselves and the world," she said. "Things don't always change for all of them, but they usually do when the kid himself wants them to. Most of them want their lives to change. When you see somebody com back to life, it can't be anything else but rewarding."

Three of the Fairfax County juvenile homes are long-term residences. Another is a short-term predispositional home for both girls and boys. All of the houseparents have their own childrens as well as the temporary youths.

"That was sort of an unexpected benefit," Mrs. Shortnacy said. "My own kids have probably learned much more about their world than they ever would have without other children living in their own home."

Those interested in participating in the juvenile program may contact Camilla Stroud at the Fairfax County Juvenile and Domestic Relations District Court (691-3145) .