Want a part-time job with Uncle Sam? Would you like to trade your present Monday through Friday shift in government for a longer day that would give you permanent 3-day weekends? Read on.

Congress and the Carter administration are working on a set of legislative and bookkeeping changes that would allow some U.S. workers to go to the 4-day week and create thousands of new part-time jobs in U.S. offices. In the process the cost of the federal payroll could go down, and service to the public could be expanded.

Phase one of the plan should be approved today. That's when the House Utilization Subcommittee is due to act on bills that would allow the government to introduce the 4-day week in some offices and also boost the number of part-time positions available.

The action would also expand the wet-your-own hours programs in federal agencies that already have 141,000 employees working some kind of flexitime" schedules from Baltimore and Reston to San Francisco.

In addition to the House legislative action, Civil Service Commission officials - prodded by the White House - are working up a plan that would allow federal managers to establish more part-time jobs without being pebalized at budget time.

First the congressional initiative: The House subcommittee is expected to approve two bills dealing with flexitime the 4-day week and more part-time jobs.

One bill would encourage agencies to increase flexitime experiments, and to increase flexitime experiments, and also waive the mandatory requirement that workers be paid oertime for work in excess of 8-hours per day. That plan would allow employees who wanted to work 10-hour days in order to qualify for 4-day week to waive their right to overtime in limited situations.

Most opposition to the voluntary waiver of the overtime law comes from AFL-CIO unions. They want the government to introduce the 4-day week, but to pay employees two hours per day ovettime in the process. The House language would permit employees to give up that overtime right in order in the bill would encourage federal agencies to expand their set-your own hours programs, which have gotten high marks from both workers and bosses in most agencies.

Allowing employees to work their own schedules with in a basic workday has virtually eliminated tardiness, increased productivity (and open hours to the public), and morale, federal officials say.

The House plan to encourage agencies - through goals rather than quotas - to hire more part-times would allow agencies to count pert-timers by the hours they work, rather than count them thesame as a full-time employee. The government now has about 39,000 permanent part-time workers, and would have more if managers had flexible job ceilings.

CSC is working with the Office of Management and Budget on a revised bookkeeping system that would make it easier for agencies will be picked - within the next couple of weeks - to begin the experiment in expanded part-time jobs under the new interpretation of personnel ceilings.

On Sept. 16, President Carter told government offices that he wanted more positions opened up to "older people, those with family responsibilities, the handicapped, students and others" who cannot work full-time, but who have talents the government can use, and who need the work. Although most people think of "housewives" when they think of part-timers, statistics show that there are about 20,000 women and 18,000 men in pwemanent as opposed to nonpermanent part-time jobs.

Outside of the Postal Service, the largest federal employers of permanent part-timers are Defense, VA, Treasury, Agriculture, HEW, and Interior. Those permanent part-timers qualify for job fringe benefits as opposed to the more than 100,000 intermittent, nonpermanent temporary workers who do not.

It will be next year before the House and Senate can approve the 4-day week experiments in government: but officials say that administrative changes opening say that administrative changes opening up more part-time jobs can be expected within four to six weeks.