NEW YORK – When New York City Mayor Bill de Blasio unveiled his “Renewal School” program in 2014, he promised “fast, intense progress” at dozens of schools that have failed students for years.

This November, de Blasio will be discussing how the city should shut down or merge some of the 78 schools in the $582 million program that made discouraging improvement in the last three years.

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“Renewal schools have not been improving any faster than the system – and that’s what he promised,” Aaron Pallas, education policy chairman at Columbia University’s Teachers College, told The New York Times.

“It’s an expensive program and the city has invested hundreds of millions of dollars in it,” he said. “And at this moment, the payoff has not been very great.”

Marcus A. Winters, senior fellow at the Manhattan Institute, made that clear in a recent analysis of student performance at Renewal schools relative to the rest of the district. Winters looked at student performance on third through eighth grade math and reading tests, and concluded the results are “disappointing,” especially considering the program’s massive price tag.

The report compares the improvement at Renewal schools to gains under former Mayor Michael Bloomberg’s school-closure policy, which shut down bad schools to allow new schools to take their place.

The Times reports:

When looking at both the 2015 and 2016 school years, the program improved schools’ scores in reading, but not math. If only 2016 is examined, students gained roughly 49 days of extra schooling in reading and 33 days of additional schooling in math, though not all grades benefited.

But even that improvement is tempered by the program’s significant price tag, said Mr. Winters. Mr. Bloomberg’s policies, he said, provided at least comparable gains at less cost in their first year — improving scores by 36 days in reading and 72 days in math.

“As noted, the academic gains generated by RSP have not come cheaply; about $1.4 million in additional annual spending per renewal school. In contrast, Mayor Bloomberg’s school-closure policy produced large gains and required little, if any, additional spending,” Winters wrote in his report, “De Blasio’s Renewal School Program.”

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“Moreover, even when failing schools improved modestly, it is an open question whether the improvement outweighs the opportunity costs … which include turning the building space into a high-performing charter school.”

“In short, these findings suggest that New York’s Renewal School Program has boosted student achievement, on average, in some of the city’s worst schools; but RSP has done so at exceptionally high cost, especially when compared with low-cost, highly effective, alternative of swiftly closing ineffective schools,” Winters wrote.

“Put in context of what could be done at a lower cost,” he told the Times, “I think it is at least disappointing.”