IN THE CITY GOVERNMENTS important effort to match teenagers with jobs this summer, Washington's larger business firms do - and should - play a major role. But the participation of smaller firms, many of them black-owned, also is crucial to the success of this year's campaign. For one thing, there are a lot of them; and they are located throughout the District. If each business with a payroll below $50,000 were to come up with one job for the city government's effort, more than 10,000 teenagers could go to work this summer.

Many of these smaller businesses are not members of the Metropolitan Washington Board of Trade, which has been assisting the District's campaign, and thus may not have been introduced to the program. There are two other organizations with long ties to the black business community - the D.C. Chamber of Commerce and the Greater Washington Business Center - that can handle inquiries and direct smaller business firms to the city's job pool.

So far, however, there are certain categories of small businesses that have yet to be heard from in significant numbers. Law firms, for example, have not been registering, even after a special pitch to them earlier this year by Mayor Barry. City officials report that only one large firm signed up with three job offers. Yet the list of job-seeking teenagers includes college students as well as a few high school students who have taken street-law courses and are interested in the field.

In the approximately 2,500 small businesses classified as minority-owned, there are many jobs in which teenagers have expressed interest but only a few offers have been made: small restaurants, neighborhood private clinics, gardening crews, moving companies, cleaning contractors, funeral homes, hotels, and small retail and grocery stores.

Obviously none of this is to say that the 50,000 or so young people who want to work this summer could all be matched with "meaningful" work that leads them into perfect lifetime careers. But there are still businesses and young people in this city who have not tried each other out, and that could forge lasting and mutually profitable relationships. Now is the right time to find out.