Last summer, as school districts across America were nervously considering whether to pry open the school doors for part-time learning, Miguel Cardona was in Connecticut, pushing districts hard to return five days a week.

Through a combination of pressure and cajoling, along with an open line of communication, Cardona saw all but one school district in his state adopt some flavor of in-person education in the fall, reopening school buildings even as teachers across Connecticut staged noisy protests and districts across the country remained online only.

That record helped pluck the 45-year-old schools commissioner out of seemingly nowhere to become President Biden’s nominee for education secretary. Biden has said one of his top goals is to open most schools. Cardona faces a Senate confirmation hearing Wednesday.

Asked if Biden’s goal is too optimistic, Cardona told Connecticut Public Radio, “No, I think it’s strong leadership to say that we need to bring our students safely back into schools.”

He emerged late in the process and the last man standing after other candidates for education secretary were nixed, largely because they were on one side or another in the intraparty battle over charter schools and other education reforms. Cardona had not taken a position on these issues, and he faced no significant objections to his nomination.

Less than two years ago, he was an assistant superintendent in a small school district, chosen for state education commissioner after Gov. Ned Lamont’s first-choice candidate demanded too much money, a state official said. Cardona was formally confirmed as commissioner last Feb. 26, the same day Lamont (D) first addressed the state’s response to the novel coronavirus.

In Republican-run states such as Texas and Florida, all schools were ordered open at the start of the school year, urged on by President Donald Trump. But the situation was different in states governed by Democrats, where fears of the pandemic and the concerns raised by teachers unions often outweighed the urgency of returning children to in-person classes.

In many school districts across the country, the choices considered were fully remote or “hybrid” systems, a part-time in-person system meant to reduce the number of students in the classroom at any given time. Many districts that began school last fall fully remote have tried to reopen since then, with mixed success.

In Connecticut, Cardona and Lamont set an expectation starting in June for full reopening. Later, they backed off and said hybrid systems would be all right, and they did not stop the state’s largest district, New Haven, from staying fully remote. But these districts had to justify their choices.

The result was that as schools prepared to launch the fall semester, debate in most of Connecticut centered on how — not whether — to reopen.

It became clear to Cardona that school-from-home was failing many Connecticut students over the spring, when the entire country lurched into remote learning almost overnight. State figures showed that some 140,000 students statewide, and possibly more, had barely attended online classes — or did not show up at all. Cardona called that a “devastating figure.”

“The inequities have really come to the surface,” he told CT Mirror. “The impact that that’s going to have — it will last generations.”

As summer arrived, Cardona and Lamont said they expected schools to fully reopen.

“We want districts to plan for all students returning in the fall,” Cardona said in late June. That means, he said, “all students back to school every day.” The state dispersed $266 million to districts to help pay for some expenses and issued public health guidance to help schools plan.

In July, Cardona sent a memo to superintendents suggesting that fully remote or even hybrid plans might not count toward the state’s requirement that children receive at least 180 days of school. That was never enforced but for a time concerned some superintendents and teachers.

“If we elected to open with a hybrid model in place, then those days would have to be made up,” Kevin Smith, superintendent of Wilton Public Schools, told his reopening committee in July. He said he was worried about the ability to safely reopen his high school in particular.

At the start of the school year, Smith decided that teachers needed a week of fully remote school before moving to a hybrid system and called Cardona to ask permission.

“That wasn’t welcome news on his end. The way he framed it was, ‘It’s temporary, right?’ I said: ‘Yes it’s a week. We need a week.’ He assented at that point.”

After that first week, all four schools in Wilton, an affluent suburban district outside New York City, began in a hybrid model, and elementary schools have since shifted to full-time in-person.

The state stopped short of trying to mandate a return to buildings. That was considered, the state official said, but it would have been “a difficult political thing to do” because Lamont would be blamed if the virus spread and people became sick. “We need to allow locals to make the decision.”

The state’s two large teachers unions staged repeated protests and issued lists of demands for reopening, only some of which school districts met. In December, about a dozen union leaders published an open letter to Lamont and Cardona with a dire assessment of the school year to date.

“Morale among educators is at an all-time low,” they wrote, demanding a pivot to full remote learning through mid-January. “Generalized fear and anxiety are widespread among teachers, staff and students. . . . Educators and students are sick.”

They said that maintaining social distancing inside buildings and keeping kids in cohorts to reduce exposure were “aspirational at best.”

Teachers and others have also complained because the state initially said schools should close if virus levels reached a certain point, but backed off that recommendation after infections soared past those thresholds near the end of 2020.

Lamont has replied that in the months since the original recommendations were set, it’s been shown that the virus does not easily spread inside schools, so schools can stay open. Still, many districts did ratchet back to hybrid or fully remote around the holidays last year.

In spite of their differences with Cardona, both large teachers unions in Connecticut are supporting his nomination.

Some teachers disagree, accusing Cardona of endangering teacher and student lives. They wanted him fired from his current job and oppose his elevation to secretary.

“Teachers are unhappy. They feel unsafe,” said Nicole Rizzo, 32, a second-grade teacher in a New Haven suburb who took an unpaid leave of absence rather than return to in-person teaching. She said there are schools with windows that won’t open, without soap in the restrooms and where ventilation systems are out of date.

“Do schools need to reopen? Yes. How they need to reopen is with resources and safely, and unfortunately from an educator standpoint that largely has not been the case here in Connecticut,” she said.

She holds Cardona partly responsible for school openings. But the statewide teachers union leaders generally praise him, saying he maintained productive and cordial relationships with all major players over the course of the pandemic.

He did so, in part, by keeping them close, holding Zoom meetings every Wednesday at 1 p.m. with state groups representing teachers, principals, superintendents and school boards. On Monday mornings, he held online discussions about the pandemic crisis with teacher union leaders.

Even when they disagreed, Cardona was “very accessible and very responsive,” said Donald Williams Jr., executive director of the Connecticut Education Association.

“We don’t always agree,” said Jan Hochadel, president of the American Federation of Teachers Connecticut. “If you disagree, he’s not going to retaliate. There’s not going to be any harm from it.”

“He always gave time to listen,” agreed Robert Rader, executive director of the Connecticut Association of Boards of Education. He said Cardona leaped quickly on myriad problems, such as how and when bus companies and bus drivers would be paid if schools were closed. “Very tough issues,” Rader said. “He brought us together with the owners of those companies.”

He also was willing to back down — notably in New Haven, the state’s largest school district, which didn’t want to go back to school buildings at all, full or part time.

The New Haven school board, supervising some 20,600 students, worried about the safety of buildings and buses, about protecting staff and students, about possible spikes in infections, and more.

“We knew there was pressure from the state to get things open,” said David Cicarella, president of the New Haven Federation of Teachers. Over the summer, he said, there was “a lot of angst, a lot of concern, a lot of worrying.”

Superintendent Iline P. Tracey warned the school board, according to minutes of its Aug. 5 meeting, that the state was pressing the board to choose between a full or hybrid opening. She and New Haven Mayor Justin Elicker, who holds a seat on the school board, favored a hybrid approach that would enable face-to-face learning two days a week.

But the board voted 4-to-3 to open the school year with all-remote instruction.

“We didn’t want to put our teachers’ and staff’s lives in danger,” said board member Darnell Goldson, who voted with the majority. He said there were too many unknowns about health and safety.

The school board had to justify its decision to the state. Not knowing how much pushback to expect, Goldson said, the board hired a lawyer to help defend its decision.

At the meeting, Cardona said he and other department heads hoped to share with the board “some facts that maybe you don’t have yet.”

He encouraged board members to reconsider but stressed that the decision was up to them. “We know each of you are passionate about the well-being of New Haven students and their success,” he said, according to a recording of the videoconference.

The state official said the Lamont administration had no interest in going to war with New Haven, especially when so many other systems were planning to reopen. “We were winning everywhere else,” he said. “If we’re going to war with New Haven, that could have damaged our credibility.”

“At the end of the day, Cardona was playing chicken with us,” Goldson later recalled. “He decided not to jump in front of that train. We hired a lawyer. We were willing to fight for our position.”

In hindsight, Elicker said, Cardona’s approach was “compassionate” and savvy. The mayor said the commissioner tried to “nudge” New Haven but did not go too far. “He could have taken a heavier-handed approach to it and said, ‘You’re all going back to in-person learning,’ ” the mayor said. But that might have backfired.

“He understood that you’ve got to work with people,” Elicker said, “particularly at this time when there’s a lot of fear. Trust is more likely to get a result than a heavy-handed approach.”

New Haven eventually came around. On Jan. 19, the district welcomed a few thousand elementary students back to the classroom for a partial reopening.