For the 18th year, the Greater Washington Board of Trade is conducting its summer jobs campaign--but with some changes: gone is the traditional "boiler room" job solicitation operation. Instead, the board is encouraging employers to provide information on job availabilities directly to their local placement agencies. For assistance from the board, employers may call 331-1414; job-seekers between the ages of 16 and 21 should contact the placement agency in their home jurisdiction, or call the board of trade for correct numbers and tips on how to prepare for interviews.

In city hall, too, officials are thinking summer: the annual mayor's summer youth program hopes to find work for 17,000 young people, with a combination of federal, local and private money. Another constructive activity for 14-to-17-year-olds is the Mayor's Youth Institute, to which 400 applicants will be nominated by church groups, schools and civic leaders. Participants will spend two weeks learning about leadership and they will then work in summer jobs; they also will reunite periodically during the school year to discuss youth issues and projects that could be undertaken in the city. Council members are to provide details on how to apply.

Just as important as jobs are the recreational programs. After a bad decision to open swimming pools late and close them early this summer, Mayor Barry has found ways and means to keep the city's 19 outdoor pools open until Labor Day (Sept. 6) and to increase activities at recreation centers. Still other efforts, such as the Send-a-Kid-to-Camp program and the Salvation Army's summer camping activities, depend on contributions from the public.

All of these attempts to help youth will still fall short of the total need--but how short is up to the adults who can offer the jobs and help finance the other activities. There is a reward, too, because this summer's youngsters are tomorrow's local work force for all seasons--and the sooner they can learn what that means, the more likely they and their employers will succeed together.