David Troup and Helen Kamioner had been out of work for some time - but as Kamioner puts it, "If you're an artist you expect to be unemployed."

Last fall, Arlington made money available for cultural endeavors under the Labor Department's Comprehensive Employment Training Act, and TRoup and Kamioner, both Arlington residents, went to work doing what they love best - opera.

Their forum became the Children's Opera Theater, a nonprofit cultural organization that spoon-feeds traditional opera to children "from 3 to 83" throughout the metrepolitan area. The opera company performs in schools, day care centers and centers for the aged and handicapped and regurlarly stages fullscale operatic productions. Itsmain thrust is introduing children to an opera, an art form the group claims can provide a powerful learning tool.

Troup, originally from New York state, had recently finished a five-year stint with the Air Force "Singing Sergeants" when he joined Children's Opera in December. Kamioner, from New Jersey, had recently moved to the area after volunteer work in theater production in New York City while living on unemployment compensation. Both are used to taking jobs wherever they could find them. Under Arlington's split most of an $11,564 grant for salaries.

Now 29-year-old Troup sings baritone for the opera company, delighting children with a voice range that can inspire delight or horror. As a production assistant, Kamioner, 27, makes the show run smoothly, helping to schedule events and keep the complicated books of a company that gets 85 percent of its $300,000 budget from CETA. Although she works behind the scenes, Kamioners exhuberance is more befitting someone who is always onstage.

"Look, I'm getting experience here I never would have gotten in New York because the competition there is so bad that extremely talented people are working in grocery stores," says Kamioner, who studied operatic voice at Juilliard School of Music in New York but chose later to go into opera management.

"Who would think anartist could go to Manpower (Arlington personnel office) and get a job tha twas in their field? It sounds too nice, I know, but I'm so grateful that the job was here - that CETA found room for the artists."

But as often happens with CETA projects, time and money is running out, and some projects fall by the wayside. Arlington has chosen not to renew CETA funding to Children's Opera, due to "simple administrative problems" with the program, according to Arlington's Manpower director Milchael Kaye denied tha tthere were way any administrative problems.

Although Arlington's participation in the program is drawing to a close, it is expected that the company will continue strong through CETA money from Montgomery county and the District of Columbia. Montgomery County this year put $161,639 in CETA money into Children's Opera, making jobs for 16 singers and stage personnel. The District funded three other positions.

Kamioner expects to stay with the company after CETA finding fo rher job runs out. She will be paid with money from the 15 percent of the company's budget that comes from local, private orgaizations. But Troup's future is uncertain because the company cannot afford to ton his salary . While the prospect of more unemployment is dismal, Troup takes it in stride. Perhaps he can do more musical revues in restaurants or hire out to sing "Happy Birthday" to somebody's wife as he has in the past.

Regardless, Troup calls his nine months with the Children's Opera "invaluable" experience for his operatic career and plans to take voice coaching in New York Cith within a year in order to join a company.

The talents of Troup, Kamioner and 23 other CETA-funded members of the Children's Theater comes together on stage. Last month, on a sunny Thursday at Wolf Trap Farm, about 50 children and their mothers gathered under a bright green tent for an introduction to opera.

Several preschoolers had more fun studying their navels or lunging after the bugs that the meadows arefull or in summer than wathcing four singers perform arias from six operas. Faces cringed and little hands went to cover ears when the soprano struck the high notes.

But the attention of most wast rapt.

The singers began the 45-minute smorgasbord of opera by identifying the parts they sang and asking the children if they could tell what voice would be best to play a prince, a witch, a king, an old man. They entertaininly described the action in operas like "The Magic Flute," "The Barber of Seville" and "The Elixer of Love." When interest lagged, they picked kids at random to play a part, a sure attention-getter.

And the end of the performance got an audible "aw" from the young audience.

"It's as much for the performers as the kids," said Kaye. "Their sense of responsibility to their audience is just as great (as to a paying, adult audience).And valuable experience which turn to them for their efforts.