Half the principals in the District’s traditional public schools were deemed “developing” — one rung above “ineffective” — on newly revised evaluations that for the first time sorted administrators by their performance.

Fourteen of the city’s 120 principals, more than 11 percent, were rated “highly effective” and were eligible for bonuses of up to $30,000. About one-third were rated “effective,” and the 8 percent who lost their jobs this past spring were rated “ineffective.”

Based on a combination of supervisor observation, test scores and other measurements of student progress, the ratings are the principals’ version of the evaluation system that has been used to judge teachers since 2009. The ratings were delivered to administrators this month for their work during the 2012-13 school year, and they drew immediate protest from principals, some of whom called them unfair and too tightly hitched to student test results.

School system officials said the ratings are an important tool for recognizing and rewarding the best leaders and for targeting areas for improvement. It should not be surprising, officials said, that so many administrators scored below effective in a city where only about half of the students are proficient on math and reading standardized tests.

“Our driving force in all our work is student achievement,” school system spokeswoman Melissa Salmanowitz said. “This evaluation system allowed us to see a clear picture of our school leader workforce.”

The D.C. school system made national headlines in 2009 when then-Chancellor Michelle A. Rhee introduced IMPACT, among the country’s first teacher-evaluation systems to link job security and pay to student test scores.

The move stirred criticism, spurred similar initiatives in other jurisdictions and drew the public’s attention to how teachers are judged. But the evaluation of the nation’s principals, who play a pivotal role in school success, has received far less attention.

That’s now beginning to change, experts say, partly because the Race to the Top competition — the Obama administration’s multibillion-dollar education initiative — gave states an incentive to start basing teacher and principal evaluations on test scores and other measures of student performance.

The District spelled out its commitment to evaluating principals based on student progress when it won $75 million under Race to the Top. Test scores and other data have been used to judge principals for several years, but this is the first time they have been compiled into a single rating.

The ratings do not significantly affect job security for administrators, who have one-year contracts and can be dismissed for any reason at the end of each school year. But the ratings do determine whether a principal will be seen as a role model and given extra leadership opportunities or whether the principal will be seen as in need of improvement and given extra attention from supervisors.

And they also determine pay. In future years, principals rated below “effective” will not be eligible for annual raises, known as step increases.

“If you have 50 percent in ‘developing,’ you know something is wrong with the evaluation tool,” said Aona Jefferson, president of the Council of School Officers, the union that represents principals. “It’s not fair. It’s not equal. These people are not failures. They’re doing outstanding work every day.”

The proportion of principals scoring below “effective” stands in striking contrast to those who scored below “effective” among the system’s 4,000 teachers. In the 2011-12 school year, two-thirds of teachers were rated “effective” and one-quarter were highly effective. School system officials have not released teacher ratings for the 2012-13 school year.

“I don’t think it’s surprising that we see higher ratings for teachers,” said Jason Kamras, chief of human capital for the D.C. public schools, who pointed out that school system officials have spent years focusing on teacher evaluations. “We’ve invested a ton of resources, energy and money into developing folks and getting the right folks and holding on to the great folks that we have.”

“Highly effective” teachers work disproportionately in ­higher-income wards, which has raised questions about whether the distribution of talent is skewed or whether the evaluation is unfair to teachers in more challenging schools. Officials declined to release a ward-by-ward breakdown for principals. The number of principals is so small that it would be impossible to preserve their privacy, schools officials said.

The evaluations include observations by instructional superintendents, who rate principals in six areas of leadership, including retaining talented teachers, engaging families and setting a vision for the school’s instruction and culture.

Separately, Schools Chancellor Kaya Henderson and principals set goals for how much the whole school and certain groups of students should improve on annual math and reading tests.

There is no simple way to say how much each component counts, but there is a blueprint for rolling them into one final rating. That blueprint suggests that proficiency rates, as determined by standardized tests, have significant weight: A principal is rated “effective” only if the school meets its testing goal in either math or reading. The principal is rated below “effective” if schoolwide proficiency in either subject stays flat or falls.

But Kamras said some subjectivity is involved, adding that supervisors can boost a principal’s rating in cases of extenuating circumstances.

“There’s no perfect system,” he said. “If we had made everything purely mechanical, there would be individuals who would say, ‘Hey, this doesn’t reflect the art of being a principal.’ ”

Kamras said the high number of “developing” principals is not a sign that the evaluations are flawed or that the school system has made poor hiring decisions in recent years.

“ ‘Developing’ doesn’t mean you’re a bad principal. It just means you’re developing,” he said, meaning that the principal didn’t reach personal goals for the year. “And we’re excited to be working with these folks to help them move up to ‘effective’ and ‘highly effective.’ ”

Two principals — one rated “effective” and the other “developing” — said that several accomplished and admirable colleagues were rated “developing” and that it hurt morale. They both spoke on the condition of anonymity out of fear of reprisal.

The “developing” principal, who is submitting job applications with other districts, said that test scores are a narrow view of success and that such ratings could deter administrators from coming to work in the District.

“I just find it disrespectful,” the principal said. “I work 70 to 80 hours a week, and I’m disappointed.”

The District has long struggled with high principal turnover, with about one-quarter of schools opening with new leaders each year.

Among the principals rated “highly effective” was Harry Hughes, who oversaw five years of sustained test-score improvements at Tubman Elementary School and who is now an instructional superintendent. Another was Anita Berger, principal at Benjamin Banneker Academic High School, a selective magnet.

Nine of the 14 “highly effective” principals worked at schools where more than half of the student body is eligible for free or reduced-price meals. The principals were therefore eligible for $30,000 merit bonuses — double that of their counterparts in wealthier schools. Altogether, the school system gave out $315,000 in bonuses to principals. This was also the first year that assistant principals received such ratings, and the performance breakdown was similar, with $105,000 in bonuses going to eight assistant principals.