“It’s a sh–t show,” one Bronx middle-school teacher remarked as she struggled to get students logged on and acclimated to remote learning.

Many of her students had no devices, she complained; others had never logged on and more had constant questions about using their laptops. Educators across the system reported similar experiences.

“We are literally flying the plane as we are building the plane,” Chancellor Richard Carranza admitted at a City Hall presser.

But why is the city Department of Education still building the “plane?”

Yes, the shutdown came as an abrupt surprise — New York was one of the last big US cities to admit it needed to close schools, though many of the city’s charters began the switch to remote learning days before Carranza and Mayor Bill de Blasio, under pressure from Gov. Andrew Cuomo, went along.

And the city had no plan on the shelf — despite all the hundreds of millions spent under the Smart School Bond Act of 2014.

That law — passed by the Legislature and ratified by voters statewide — was designed to help schools access high-speed broadband, expand learning outside the classroom and acquire technology and devices. It short, it should have laid the groundwork for the “distance learning” now being invented on the fly.

It yielded $783 million for the city Department of Education, which reported that in December the state authorized earmarking about $250 million for digital (Wi-Fi/wired) infrastructure and $133 million for devices, along with $300 million for temporary classrooms called “transportables” and $100 million for PreK classrooms.

Yet DOE officials estimate that more than 300,000 city students still lack access to working PCs or tablets now. And few teachers had any training in remote learning as of just two weeks ago.

We have confidence that most city teachers, students, principals and school staff will work it out — as that Bronx teacher concluded after the first day of online classes: “It can only get better from here.”

Too bad the central DOE bureaucracy, despite vast resources and years of lead time, didn’t give the front-line educators a better hand to start with.