Slow learner Bill

Mayor de Blasio is learning from painful experience what careful study of the evidence should have taught him from the get-go: that Mike Bloomberg’s approach to chronically failing schools — closing them and letting kids get a better education elsewhere — made a hell of a lot of sense.

As de Blasio slowly awakens, finally announcing plans to shutter six woefully underperforming schools, thousands of kids remain stuck in classrooms where real teaching and learning may never happen.

In November 2014, the mayor stood before the city exuding moral conviction that a humane new approach to the city’s worst schools, now christened Renewal Schools, would yield dividends that mean old Mayor Mike failed to deliver.

As de Blasio caricatured it, under Bloomberg “teachers were hamstrung,” parents and students were “written-off” and “put down,” and schools were summarily shut down long before they had a chance to change.

In fact, the Bloomberg strategy — phasing out chronically failing schools with rock-bottom academic results and corrosive cultures, and opening new schools, both district and charter, in their place — helped kids. Reams of research confirms it. Under de Blasio’s watch, Chancellor Carmen Fariña began pouring upwards of $180 million a year into nearly 100 schools, layering on community programs, additional instructional time, teacher training and more. The money would buy progress, they promised, and no excuses.

“We will demand fast and intense improvement — and we will see that it happens,” said de Blasio.

That bold pronouncement proceeded to slam into the brick wall of reality. Enrollment in the schools has fallen, from 44,000 in 2014 to 37,000 this school year. And though results are uneven, by many indicators progress has been halting.

The Department of Education insists that the program is on track — with chronic absenteeism down, attendance up, graduation rates up slightly and two-year jumps in test scores.

Surely there have been some successes. But even granting those results, it’s hard to see how they add up to sufficient bang for the buck in what works out, in rough math, to nearly an extra $4,800 per enrolled kid per year.

And despite all that focused attention and funding, at slated-for-closure Leadership Institute in the Bronx, enrollment is plummeting. At Monroe Academy for Visual Arts and Design, the graduation rate is now an abysmal 38%.

At JHS 162 Lola Rodriguez De Tio, just 3% of students are doing math at grade level, and just 9% are passing state English tests.

It is only a matter of time until the mayor’s costly and time-intensive turnaround strategy itself becomes the target of a turnaround.