More New York City fourth-graders met statewide English Language Arts standards than ever before, a grinning Mayor Bloomberg announced yesterday as he joined his schools chancellor, Joel Klein, in cheerleading for the impact of his education policies on student performance.

The percentage of fourth-graders meeting or exceeding standards rose by 9.9 percentage points in New York City, to 59.5%, compared to an 8.2 percentage-point gain statewide, to 70.4%.

Eighth-graders, whose test scores were also released yesterday, did not fare as well.

The percentage of city eighth graders meeting standards fell by 2.8 points to 32.8%, compared to a 0.9-point gain statewide to 48.1%.

The figures mean the city’s fourth-graders’ scores topped the statewide gain by 1.7 percentage points, but the statewide change in eighth-graders’ scores was 3.7 percentage points better than the city-only scores. The New York City public schools have about one third of the statewide enrollment.

The mayor acknowledged the eighth-grade scores were “disappointing” but said his administration had focused first on the city’s youngest children and has seen positive results.

“Through a stronger core curriculum, focused intervention programs, and our Summer Success Academy, we’ve redirected kids who were riding a trajectory to failure and steered them onto a path to success,” he said. “A lot of people were nervous about our decision to end ‘social promotion,’ but those concerns have proved to be unfounded. Instead, we’ve shown just what can be accomplished when you set high standards for students and give them the help they need to meet those standards.”

Mr. Bloomberg said last year’s lowest-performing regions made the most gains. Fourth-grade scores in Region 1 in the Bronx jumped 19.9 percentage points, for example.

He also said that students who failed the third-grade test last year but were ultimately promoted to the fourth grade under the new promotion policy did not fall back to the lowest level on the fourth-grade test. Indeed, 15.8% of the 3,785 students who originally failed the third-grade test leaped to Level 3 from Level 2, while 10.9% of those students dropped back to Level 1.

The mayor also announced plans yesterday to pour $40 million into a new strategy to help struggling middle-schoolers. The plan extends the Saturday Prep Academy, which now serves fifth-graders, into middle school, and promises financing for teacher training and programs to help students improve their reading skills.

As the mayor stood in a third-floor classroom at P.S. 33 in the Bronx to make the announcement, the four Democrats running for mayor were busy sending e-mails to reporters, questioning the gains and criticizing the mayor’s education policies.

The City Council speaker, Gifford Miller, said: “When over 40% of our city’s fourth graders and almost 70% of eighth graders are still failing to read at grade level, that’s not cause for celebration.”

He said the mayor should be concentrating on “the fundamentals of student achievement,” including smaller classes, better teachers, and safer schools.

The Manhattan borough president, C. Virginia Fields, said: “Some part of the increase in the city’s score is attributable to a state regulation allowing schools to remove English Language Learners (ELLs) from the reading tests. The city’s reading scores may be inflated, particularly in districts containing many ELLs.”

The former Bronx borough president, Fernando Ferrer, also said the department had “inflated” results by exempting struggling English learners from the test.

The Department of Education said only 900 additional students took advantage of a new state regulation allowing children who have been in America for four or five years to take the New York State English as a Second Language Achievement Test instead of the English Language Arts exam. Even if all the students had taken the ELA exam and scored at the lowest level, the department said, it would have had only a tiny impact on the citywide average.

Rep. Anthony Weiner of Queens also accused the department of manipulating the population of test-takers.

“Kids who did better on this year’s tests should be congratulated,” Mr. Weiner, whose district also includes part of Brooklyn, said. “But let’s be clear. There’s a couple of ways to improve test scores. One is by improving performance of students and teachers. As mayor that’s what I would do. The other is by fudging the test and who’s involved in it. It looks like the mayor and the chancellor are choosing this route.

“They’ve taken out of the testing pool those students who are generally the bottom performers,” Mr. Weiner said. He called for more transparency at the education department and said: “The mayor shouldn’t cheat on the test results.”

The mayor and chancellor said there was no cheating involved and implied that their political opponents were trying to mislead New Yorkers with data.

“Anybody can use selective data,” Mr. Klein said. “We know what the real numbers are.”

Mr. Bloomberg dismissed the Democrats’ criticism, saying: “Maybe it’s just time that people stopped and said when we really have some good news we should enjoy it. We’re talking about our children, we’re not talking about politics. We’re talking about the future of our country and all of the teachers who worked so hard this year to improve the educational system. Alleging that they are cooking the books or that nobody’s really recording what’s going on really just isn’t fair to them.”

According to experts on city politics, no matter what the Democrats said yesterday, the news of rising fourth-grade test scores will help Mr. Bloomberg convince voters that he has lived up to his pledge to be the “education mayor.”

“They’re gaudy numbers. They’re impressive numbers, and it’s going to be hard for the opponents to cast them as a legacy of failure,” a professor at Baruch College, David Birdsell, said. “Clearly the mayor’s hand has just been significantly strengthened.”

A longtime political consultant, Hank Sheinkopf, said: “The Democrats would be happier politically if scores had gone down. The fact that scores have gone up makes it more difficult to make an argument that resonates with voters.”

Still, he said, as New Yorkers prepare to vote in November, the candidates will continue to talk about schools.

“They’ll talk about schools because to some extent, perception won’t meet reality,” he said, adding that the mayor’s political opponents would be smart to highlight problems in the schools, including overcrowding and under financing, rather than test scores.

Outside the realm of politics, reactions to the test data were more varied.

The chairwoman of the City Council’s Committee on Education, Eva Moskowitz, questioned the gains, saying the 10-point rise “makes one wonder if the test was easier or graded differently, or if something else changed at the state level.” She called for more “number-crunching.”

The director of the Center for Research on Teaching and Learning at New York University, Robert Tobias, said large statewide gains indicated “students found the test easier this year than in the past.” He also said his preliminary calculations demonstrate “the districts that are showing the biggest increases retained more students” in third grade.

The president of the teachers union, Randi Weingarten, said elementary school teachers and students deserve credit for the scores. She said the scores prove that when “teacher input is welcomed” there are positive results, underlining the 20-point gains in District 9 in the South Bronx, where some teachers have received extra pay in exchange for mentoring new teachers.

“It’s a concept that is similar to our proposal for a career ladder and an enterprise zone to pay differentials to attract the best teachers to the lowest performing schools,” she said. “We need to have a laser-like focus on those low-performing schools to pull up our most vulnerable students.”

She also called on the administration to “stop the contract-bashing” and work out a contract with the teachers.