Mayor Michael Bloomberg, Schools Chancellor Dennis Walcott, and Deputy Chancellor Shael Polakow-Suransky walked reporters through a powerpoint presentation on the city’s latest test score results.

This afternoon, Mayor Michael Bloomberg enjoyed what could be his last opportunity to point to clear gains on city test data.

The state is overhauling its testing program next year, and year-to-year comparisons favored by Bloomberg’s test analysts will soon become futile.

Until then, city officials are championing the small gains almost every group of students made on this year’s state tests, calling the scores a sign that some fledgling school initiatives are already working.

Breaking the test results down by race, grade level and students with disabilities, each group saw gains of one to four percentage points for the numbers of students scoring proficient on the literacy and math exams. But students of color are still performing well below their white peers, and the number of English Language Learners scoring proficient in literacy actually dropped by 1.8 percentage points.

“There is still a gap, and it is unacceptable, inexcusable and it is our responsibility to rectify it,” Bloomberg told reporters this afternoon.  He speculated that the ELL scores dropped because the city has begun declassifying greater numbers of ELL students who have become proficient in English.

The much-touted Young Men’s Initiative would help overcome the racial performance gap, Bloomberg said. He attributed minority students’ gains to the early efforts of that initiative and two others: the push toward aligning lessons to new state standards called the Common Core, and the Department of Education’s plans to improve middle schools.

Last year, Chancellor Dennis Walcott said he would make boosting poor eighth grade literacy scores the focus of his Middle School Initiative. In 2011, the number of eighth graders scoring proficient on the literacy exams dropped. This year that number increased by 4 percentage points.

“Congratulations,” Bloomberg said to Walcott, striking a cheerful tone as he stepped away from the podium at a press conference, “This is an accomplishment you’re going to look back on for the rest of your life.”

Teachers union President Michael Mulgrew praised the middle school gains in a statement, but cautioned that the city had more work to do to close the racial achievement gap, particularly in literacy.

“Not only do black and Hispanic students still lag well behind whites and Asians,” he wrote, “but in the ELA results the gap actually widened this year.”

Another improvement Bloomberg heralded in the press conference were the gains charter schools made. On average, city charter school students gained seven points in English, and 3.5 points in math.

“Progress is especially evident, you know, in our charter schools,” he said, adding that 24 more charter schools will be opening in the city in the fall. “Charter schools are phenomenally popular for people who know where it really matters to them… We can’t possibly handle the demand from parents for the charter schools they’re just off the charts.”

Critics say these results mean less than they did in years past because the exams are poised to change dramatically to reflect the new Common Core State Standards, and because several poorly written test questions had to be thrown out.

Bloomberg waved off the suggestion that the test results are less valid, singling out one infamous question about a pineapple that set off flurry of testing criticism last spring.

“No matter how much you argue that the pineapple was a ridiculous question, every kid in the state had the pineapple question,” he said.

Deputy Chancellor Shael Polakow-Suransky said schools could use this years data to see how well they are teaching certain academic skills, even though many will be reinventing their test preparation strategies before next year’s new exams.