Uncle Sam will hire about 14,000 high school and college students for summer jobs in agencies here this year. For the first time, people seeking temporary clerical positions that pay from $7,960 to nearly $11,000 to start will not have to take tests. If you want one of the jobs, now is the time to act.

There are two main summer job programs. The so-called stay-in-school program for needy youth is handled through high schools and colleges. Students register for the jobs. Schools put them in touch with agencies that are hiring people for a variety of positions.

The "regular" summer job program is open to high school and college students. Jobs range from cerical and custodial to various technical and scientific aides, jobs in food service and as lifeguards.This is what you do:

First get a copy of Summer Job Announcement No. 414. It can be picked up at most federal personnel offices, or at the Office of Personnel Management at 1900 E St. NW. It tells where many of the jobs are, what they are and where to apply for them.

Next, get the Job Applicatuoin Form, OPM 843a. It is also available at agencies, at Federal Job Information Centers here and around the country, or from the OPM itself. (College students should also get Form 1170. It lists courses they are taking and will help employing agencies decide who to hire for what kinds of jobs.)

Fill out the forms carefully and mail or hand-deliver them to the agency or agencies where you would like to work next summer. Each agency will require a separate form or copy of the form you have filled out. People who took summer job tests last year must reapply like everyone else.

Under new decentralized authority, agencies have considerable leeway as to whom to hire, and how they pick people they want to hire. Army, for example, will weed out applicants via the last four digits of their Social Security number. The lower your number, the better chance you have of being considered. Other agencies will use different methods to determine who to consider. Bear in mind that in some cases there are hundreds of applicants for each single job.

In most agencies the filing period ends April 15. But check Announcement 414 carefully since some agencies have earlier closing dates. You can file immediately -- many have already applied. But you cannot file after the agency job closing date and expect to be considered, much less hired. A full list of the agencies that have summer jobs is available in Announcement 414. Here is a partial listing of agecnies with summer jobs. In every case, send the application to the Summer Employment Coordinator.

Agriculture Food and Nutrition Service, Room 718, 500 12th St. SW, zip code 20250 for GS 3/4 typists . . . Agriculture Food & Quality Service, Room 3438, South Building, 14th Street and Independence Avenue SW, zip 20250 for GS 3/4 engineering aides/technicians, mathematics aides and biological aides. Agriculture also has openings in Beltsville for biological aides and biologists (GS 5), accounting and library technicians, and typists.

Army has typist and steno jobs (40) in Alexandria, Room 2W17, 5001 Eisenhower Ave., and openings for computer aides, procurement clerks, typists, engineering draftsmen in Berryville, Va. Address is P.O. box 2250, Attn: MEDPO-S, Winchester, Va., 22601.

Navy will hire about 100 summer typists and stenos, at Grades 2 through 5. Send applications to Room 500, Bldg. 6, Crystal Plaza, zip 20360.

Department of Education has jobs in business, computer science, accounting, statistica aides, education research assistants, GS 3-4 downtown. It has a few higher grade jobs for persons in education research assistants, GS 3-4 downtown. It has a few higher grade jobs for persons in educatuon research, public administration, social science and business. That is Room 1100, 400 Maryland Ave. SW, zip 20202.

Federal Communications Commission will have engineering, physical science, computer science, communications aides/technicians jobs at GS 1 through 4 and some law student assistant, economics, electronic engineers, computer sciences, public-business-political science openings at Grades 5 and 7. That is Room 208, 1919 M St. NW, Zip 20554.

There are many more jobs. Check Announcement 414 for details. And good hunting.