The District of Columbia is searching for a new school chief now that Julius W. Becton Jr., a retired general drafted to run the troubled system, is quitting at the end of the academic year. He was on the job for 16 months.

"I'm tired, I really am, physically, emotionally, mentally, I'm tired," the 72-year-old Becton told a news conference Thursday. "This job has been the toughest job that I've ever had."Mayor Marion Barry Jr., however, said Becton "was the wrong person for this job . . . schools are worse off today than they were a year ago."

A control board created by Congress to pull the nation's capital out of a financial crisis took over the public schools, fired the previous superintendent and put Becton in charge in November 1996.

The district's 77,000-student school system has been plagued by crumbling buildings, poor test scores, violence and mismanagement so severe that officials were unsure how many employees were on the payroll.