#It’s time for the Department of Education to reopen the schools

Remote learning was off to a fine crash-and-burn Wednesday, with big problems all across the city. Worse yet, many teachers are determined not to show when in-person schooling resumes in a few days — under any condition. Mayor de Blasio nonetheless vows schools will open Monday. He needs to stand tough.

“The mayor’s reopening plan is not safe,” huffed a teachers-union caucus, the Movement of Rank and File Educators. It blasted the city for “inadequate contact tracing and a lack of transparency” and threatened that teachers wouldn’t return until they’re satisfied — which looks like never.

United Federation of Teachers boss Mike Mulgrew cited a “major staffing challenge.” The city is adding 2,000 teachers, but principals-union head Mark Cannizzaro says 10,000 are needed. Indeed, the hapless Department of Education dropped the news late Tuesday that roughly half the children slated for “blended” learning may have no direct contact with a teacher on days when they’re logged in from home.

It’s a mess. This is a system, after all, run by a race-obsessed chancellor whose hires have left the bureaucracy even more inept than usual.

But the city is taking countless steps to make schools safe. It set up testing routines, contact tracing, ventilation procedures, hybrid schedules and numerous other measures. Kids whose parents have concerns can opt for online instruction only. Teachers with serious medical issues can get exemptions.

As for the “staffing challenge,” de Blasio got it right: “I’ve never met a manager [who] didn’t want . . . more personnel,” he snarked Tuesday. If gaps remain, he said, his folks will address them. That’s eminently reasonable, yet not good enough for some teachers and ­union leaders.

What a contrast from, say, health-care providers, police or transit workers — all of whom reported for duty at the pandemic’s height despite sky-high infection rates and triple-digit daily death tolls. This week, the infection rate has been below 1 percent; Monday’s death toll: seven. Of 17,000 school officials tested, only 55 (i.e., 0.32 percent) were positive.

Meanwhile, online-only learning remains a virtual joke. Teachers spend much of the day just getting students to log on and pay attention — and that’s when the system can avoid the glitches that plagued the first day of school. Many parents are counting on kids in school at least part-time so they themselves can work.

Another delay would mean cheating children of anything close to a real education, while wreaking havoc on their parents’ lives.

De Blasio admits the system won’t be perfect. And some teachers and kids will contract the virus.

Some “will test positive,” he noted, and they’ll “immediately get support.” Infected students will “go home for two weeks,” and then come back and complete the school year. “For the very small percentage of people who test positive for the coronavirus, it is a very temporary reality.”

He’s absolutely right, even if it’s politically incorrect to say. As the Centers for Disease Control and Prevention reports, 94 percent of COVID deaths have involved people with an average of 2.6 other conditions; 92 percent were 55 or older, an age when many teachers have already retired. Younger people often don’t get sick or, if they do, recover quickly.

So what happened to “follow the science”? Doctors and scientists (the American Academy of Pediatrics, for example) stress that the benefits of in-person school outweigh the dangers of COVID. Fact is, it’s vital to get kids out of the house, away from screens and back in class.

De Blasio vows the system will open for in-person instruction Monday. Yet he also promised they’d open Sept. 10, before caving. For the sake of the kids, parents — and science — he best not buckle again.