Closing schools is painful. But in Boston, it’s essential.

Just as a budgetary matter, it doesn’t make sense to maintain so many unused seats. But the core problem posed by under-enrolled schools isn’t financial. Students’ educations are harmed when schools have so many empty seats that it’s not viable to offer sports teams, clubs, and a wide variety of classes.

“When some of the schools are larger, but then some are very small, at that tiny scale, it’s very, very difficult to sustain the range of academic offerings” and extracurriculars that students, “especially high schoolers,” need, the mayor said last year.

The Globe profiled one of the high schools bearing the brunt of enrollment declines last year. The Jeremiah E. Burke High School in Roxbury, where enrollment is half what it was two decades ago, lacks extracurriculars like a school newspaper and the range of academic offerings that other high school kids take for granted.

Districtwide, 32 of the 119 school buildings have “utilization rates” below 84 percent over the past five years — which the district considers “not ideal.” And several enroll less than half their capacity. The five-year utilization rate at the Burke (which was recently renamed Albert D. Holland High School of Technology) is 58 percent, according to the district.

A long-range facilities plan released by the district in January suggested that as many as half of the district’s buildings could close in the most extreme realignment scenario, though Skipper said the district wasn’t contemplating closing that many.

There are many reasons for the enrollment decline, including the inescapable demographic reality that families are having fewer children. BPS also faces competition from private, parochial, and charter schools, as well as from the Metco program, which buses some Boston kids to suburban public schools.

The problem has been known, and largely ignored, for years. In 2013, this editorial board wrote that “[d]emographic shifts point to sparsely attended high schools for many years to come.” Two years later, an audit commissioned by former mayor Martin Walsh said the district could save millions by closing undersubscribed schools. At the time, BPS served about 57,000 students; the figure was just under 48,000 last year.

From a political standpoint, mayors know they’ll take plenty of heat from teachers and parents for school closures — but likely won’t get credit for any of the long-term improvements that might result from an efficiently run district that spends more of its money in the classroom and less on heating, maintenance, and duplicative staff. When spring 2024 came and went without any major closures or consolidations, some education advocates feared the Wu administration was joining its predecessors in kicking the can down the road.

Still, Skipper said in an interview with the Globe editorial board last week that addressing the district’s facilities was a high priority. “We see this as urgent work,” she said.

If Wu and Skipper are serious about finally right-sizing the district, they deserve the public’s support through what is bound to be a contentious process. But the public deserves something too: a specific and detailed vision from the city, with measurable goals, for how the district will reinvest money freed up by consolidation.

The downsides and dangers of school closures are abundantly clear. They’re disruptive for parents, staff, and students, and can harm neighborhoods that lose local institutions. Children from closed schools can feel stigmatized, especially at the high school level. In cities that did not handle closures well, such as Chicago, they have dealt academic setbacks to some affected students.

But those are reasons to approach closures carefully, not reasons to avoid them. The cost of not closing and consolidating schools is high, too, even if it’s harder to see. A conservative estimate is that the district would realize about $40 million in annual savings if it had no under-enrolled schools; that’s what the district pays in “soft landing” funds to schools whose enrollment goes down (the district’s overall budget is about $1.5 billion).

Over the next few weeks, the Globe will outline some ideas for better ways the district could use that money — adding more high-dosage tutoring, for instance, or offering more bilingual education. It’s not meant to be an exhaustive list. But those are the kinds of ambitious investments that the district should be promising to students and families as schools are closed, merged, and reconfigured. The goal should not just be fewer schools, but fewer schools that are consistently better.

In an interview with the editorial board, Wu said that school reconfigurations would be “a multiyear process to manage transitions thoughtfully and individually” and that her promise to families was a “guarantee that every person who is disrupted by this, it’s because there’s benefit that they experience from it.” The district has developed a rubric to evaluate schools that focuses on three main criteria: the utilization rate and two measures related to the building’s physical characteristics.

Wu and Skipper didn’t offer a specific timetable but said some changes could be voted on by the School Committee in spring 2025. Wu said the process would leave “enough planning time for families to adjust and and plan their lives around it.”

Let’s hope they stick with it and succeed. Education is vital to maintaining Boston’s viability as a top-tier city. More than ever, the city needs to prepare students for careers in a changing economy and hold onto middle-class families. To accomplish those things, quality schools for all students are essential. As painful as it will be, the process that the city is contemplating is essential to meeting those goals, both by getting kids out of under-enrolled schools and investing the savings back into education.

Opposition — and there’s almost certain to be opposition — will focus on the hardships of closing schools, which are real. But Wu, Skipper, and the city’s political and business leadership can’t cede the conversation to skeptics who dwell only on those downsides. At every opportunity, officials ought to be offering a positive vision for how reconfiguring the district is a chance to give more students in Boston what every one of them deserves: a quality education.

Editorials represent the views of the Boston Globe Editorial Board. Follow us @GlobeOpinion.