Six hundred of the 32,000 District youngsters hired under the city's ambitious Summer Jobs for Youth Program are still waiting for paychecks, six weeks after the project ended.

The number stood at double that figure late last week. But since then, the city's payroll office said it had issued checks to 600 young people after it received the required records from the city's Department of Labor.

The remaining teen-agers could be owed from one to three checks, department spokesman Adolph Slaughter said.

The highly publicized jobs program had been plagued by confusion and erratic payments since it began in June. This year, though, it gave double the number of jobs to young people that it did the previous summer.

The number of delayed payments has been cut in half in the last few days, he said, because, "we have been working very hard. People are working around the clock. This is no joke when kids are not paid."

Slaughter said in the department's payroll section was beefed up from nine to 15 persons in mid-September "as the problem escalated." There are currently 18 employes at work verifying payments, he said.

The department cannot determine the total amount of the deliquent payments because the teen-ager are paid varying amounts and worked varying hours, Slaughter said.

He said the check delays were caused by supervisors submitting inaccurate information, teen-agers attempting to collect more money than they were eligible for, and incomplete certification of each employe.

"We're not on the job site," Slaughter said. "We have 1,400 job sites and they have supervisors that must submit the payroll information."

In addition, he said, "a lot of kids thought they could beat the system" and work two jobs instead on one. When the department's computer system received a request for a second check, that request was rejected. Now some of the young people have complained that they have been paid for only one of their jobs.

In other cases, teen-agers had signed up for their jobs incorrectly and this delayed their checks, he said.

Ernestine MCCombs, 15, of 720 Shepherd St. Nw, said the city government still owes her $108 for her last week of work as a receptionist at the University of the District of Columbia.

"I went down to the headquarters on Sept. 18 and they had no check for me and I've been calling and calling since and I still have not gotten my money," she complained yesterday. "I know a lot of people like me."