School officials said the vote sets the stage for a confrontation with Schools Chancellor Joseph A. Fernandez, who has previously dismissed principals and superseded local boards.

Dr. Crew said he was determined to "pay attention to the real prize," and continue his efforts to turn around failing schools, dismiss incompetent principals and infuse the system with technology that would help students meet higher graduation standards.

In less than a month in office, Mr. Fernandez has reached down into the heart of the city's decentralized system to bypass local school boards and remove one superintendent, block the appointment of another and dismiss principals.

The plan has produced controversy in at least two predominantly Hispanic schools, where parent councils were accused of racial bias in dismissing white principals.

To prod schools to improve, states and districts have tried any number of strategies, from ordering the full-scale replacement of curriculums to dismissing principals to imposing layers of standardized tests.

Speaking at a news conference, Jill S. Levy, president of the union, the Council of School Supervisors and Administrators, said she did not fault Mr. Klein for seeking to dismiss poor principals.

Even dismissing incompetent principals will not turn the whole system around.

Dr. Crew also won power from the Legislature last year to dismiss incompetent principals and superintendents, though some parent advocates and board watchdogs have criticized him for not fully exercising the right.

Mr. Zacarias promised to focus on the 100 lowest-performing schools in the district and to dismiss teachers and principals if test scores did not improve.

Although the governance law was credited with establishing clear lines of accountability, a crucial step was left out: the law did not fundamentally alter the procedure for dismissing principals.