An earlier version of this story misspelled the name of a Rivet School student. It is Chris Clausen. The story has been corrected.

PORTLAND, Maine — The ergonomic chairs, glass-walled conference rooms, ubiquitous technology and smell of new carpets and fresh paint scream well-funded start-up.

And that’s what the Roux Institute is: a brand-new university campus backed by $200 million of donated money.

The institute, which opened last year in borrowed space in Portland’s East End, is offering master’s degrees, certificates and professional training in computer science, data analytics, artificial intelligence, biotechnology, cybersecurity and other subjects.

These are hot fields in a state with a growing tech sector that employs 12,140 people but whose existing colleges and universities collectively produced only 103 computer science graduates with bachelor’s degrees or higher in 2017 — the last year for which the figures are available — including just 10 with master’s degrees.

“Nobody was servicing the need,” said Chris Mallett, the chief administrative officer.

At a time when other higher education institutions are closing or merging because of a decline in the supply of high school graduates, the Roux is among a small but largely unnoticed number of new colleges that are opening.

Some are focusing on high-demand disciplines such as technology and alternative energy. Others are serving the huge number of Americans who never went to college or completed a degree. Still others are trying to remake higher education with new models that forgo top-heavy bureaucracies and expensive campuses — models that in some cases don’t look like conventional colleges at all.

All three strategies are in large part a reproach to traditional higher education, which has often failed to provide the right programs to the people who increasingly need them.

It seems a bad time to start a university or college. Postsecondary enrollment has been falling since 2011, with particularly big dips last year and this, according to the National Student Clearinghouse Research Center. In the last five years, more than 60 conventional colleges have closed, merged or announced they will close.

“You get the combination of ‘That’s so brave of you,’ ‘It’s admirable’ and ‘You’re crazy,’ ” Michelle Jones said of people who hear that she founded a new associate degree-granting college — Wayfinding Academy in Portland, Ore.

But several postsecondary institutions have opened or are about to debut.

The Roux, for instance, was started after Maine native David Roux, chairman of the private investment company BayPine and co-founder of the technology-focused private-equity firm Silver Lake, offered $100 million to create a technology-focused university in his home state. A Maine-based foundation kicked in another $100 million.

Roux and his wife, Barbara, ultimately teamed up with Northeastern University to run the project, which was given temporary space in a tech company building on the Portland waterfront and reports enrolling 313 students this semester.

Also in Maine, Unity College plans to launch the Technical Institute for Environmental Professions in the spring at a new campus that will award certificates and associate degrees to people who want to work in fields such as solar power. Demand for workers in solar is expected to nearly double by 2030, according to an industry census.

Bristol Community College in Massachusetts is converting a former seafood packaging plant into an offshore wind institute scheduled to open next spring. The number of workers needed in the offshore wind energy industry will also nearly double, by 2025, to 589,000, and increase to 868,000 by 2030, the consulting firm Rystad Energy estimates.

Others of these new efforts are dramatically different from traditional higher education experiences, and their focus is almost entirely on nontraditional students.

The Rivet School, with campuses in Richmond, San Francisco, Oakland and San Jose, Calif., provides personal coaching, financial aid, group study sessions and career counseling to 164 adult students — a large proportion of them working and more than half of them parents or caregivers, the founders say — who take courses on their own schedules from two accredited nonprofit online universities.

Students graduate with a certificate of completion from the Rivet School. To them, it’s a college — the conduit through which they get degrees, even though the degrees are in the name of one of those two universities.

A program with intensive advising similar to the Rivet School’s, called Duet, in Boston, resulted in graduation rates that were double the state average, while cutting the cost of college in half, a Harvard study found.

“There’s a huge opportunity to rethink what the college experience looks like,” said Jeff Manassero, the Rivet School’s executive director.

Many of his adult students complain that conventional colleges failed to help them balance school with families and jobs.

“It was very much like a factory,” said Chris Clausen, who started college after high school but never finished and now, at 29, has returned to take courses at the Rivet School toward a degree in business management.

In a knit cap and long-sleeve raglan T-shirt, Clausen was hovering over his laptop in Rivet’s Richmond outpost, not far from the shipyard where women were recruited into service during World War II by a poster featuring the fictitious Rosie the Riveter, from whom the school took its name.

“There’s just a lot of hurdles in traditional colleges — financial aid and choosing classes and picking majors,” said Chardonnay Hightower-Collins, a coach at Rivet. “That’s why we exist. We’re filling the gaps.”

Back east, in Pennsylvania, college and university enrollment has declined by 22 percent in 10 years — so much that the public university system is combining six of its campuses into two regional institutions. Yet one Pennsylvania county in September opened its own new community college.

Erie County Community College, or EC3PA, has used federal pandemic funding to make tuition free and is offering courses and services virtually and in person at a vocational high school, branches of the county library system and an education center run by nuns.

“We’re never going to build some 800-acre campus,” said Chris Gray, the founding president.

EC3PA, too, focuses on students who its advocates say are not well served by existing universities — working adults with children, for example.

“What made me pack up my family and move and take a risk at a time enrollment’s been horrible is that we have to rebuild this system from the ground up and tear down those things that keep traditional higher education so elite,” Gray said.

Wayfinding Academy co-founder Jones previously taught organizational behavior and leadership at Concordia University Portland, which closed last year because of growing debt and declining enrollment. Even before Concordia shut down, she and others raised $200,000 to open Wayfinding, which offers one major, called self and society, meant to help students decide on what they want to do in life.

Wayfinding has 25 students — 70 percent of whom started but never finished at traditional universities, Jones said — making it part of a micro-college movement that rejects huge, impersonal universities, even at a time when small colleges are struggling because of poor economies of scale.

Flagstaff College in Arizona, for example, also has only one major, sustainability and social change, and operates out of space on a community college campus. Other micro-colleges in various stages of development include Outer Coast in Sitka, Alaska, housed on the campus of a conventional college that closed in 2007, and Thoreau College in Viroqua, Wis. Those schools also have smaller staffs and lower overheads, with administrators often taking on several roles.

These kinds of places are “for folks who for whatever reason, and there are a lot of them, wouldn’t thrive in the traditional college model but still want college,” said Jones.

“Everybody agrees that our higher education system is broken,” she said. “They might disagree about what needs fixing first. But everyone is aware of the brokenness.”

Conservative founders and supporters of another just-announced institution, the University of Austin in Texas, say they will open next summer as a counterbalance to “illiberalism.”

It isn’t easy to start a college. Unity’s new campus was scheduled for a September opening, which has been pushed back to the spring. A performing arts college planned by the nonprofit Norwalk Conservatory of the Arts in Connecticut announced plans to open in August 2022, but that has now been moved to 2023.

Nonetheless, Hightower-Collins, at the Rivet School, thinks the momentum will continue.

“That’s just the nature of the world at this moment,” she said. “We’re finding all kinds of gaps in society, and you see so many start-ups popping up to address those problems.”

This story about new colleges opening was produced by The Hechinger Report, a nonprofit, independent news organization focused on inequality and innovation in education.