As schools grapple with responding to the new coronavirus and the federal government’s recommendation to plan for extended closures, one thing is becoming clear: remote learning remains a remote possibility.

An escalating number of COVID-19 cases are being confirmed in the U.S., and at least nine deaths have been reported as of Tuesday afternoon, making extended school closures in some communities more likely.

Most school districts do not have plans for continuing instruction during an extended closure, but several are considering it after the Centers for Disease Control last week urged districts to prepare. This has opened up an opportunity for tech companies trying to market products enabling distance learning, though experts caution districts not to rush into making big investments.

Several challenges stand in the way besides the cost of new software or infrastructure. In many communities, large numbers of students don’t have internet access at home. Other students, such as those with special needs, may need the services they would get in person at a school. All of this means that a switch to remote learning could worsen longstanding equity problems.

In areas where the virus has appeared, some school districts have already cancelled class for a couple of days to clean buildings, or to let teachers spend time learning how to conduct online lessons. That includes the Northshore district in Washington state, which has the most confirmed coronavirus infections in the country. And an Oregon district that employs that state’s first COVID-19 patient closed the school that person worked at, while keeping kids in class in other schools.

Children do not appear to be at high risk of getting seriously ill themselves, but may be able to spread the virus to others, including school staff.

In New York, where two cases have been confirmed this week, the State Department of Education “strongly encourages schools to send classroom work” to students who are under quarantine. The department recommends posting assignments online or the old-fashioned way: by mailing work to students’ homes.

New York City officials have not indicated whether any plan is in place for remote learning.

“I think we’re not there yet,” Mayor Bill de Blasio said Tuesday. “The model we’re working on right now does not involve school closures.”

He added: “We’re not doing alternatives until we have to.”

Still, companies are jumping at the opportunity to showcase products in districts that are at least considering remote learning. This week, the for-profit education company K12, one of the largest providers of online curriculum in the country, started contacting school districts in counties that have been affected by the new coronavirus in Washington and California to offer their services in the event that schools are closed.

Scott Durand, a K12 senior vice president, said the company is prepared to offer access to its online learning platform and curriculum for free for the first month or so, though districts would have to pay for training on how to use it. If schools were closed for longer than that, Durand said, they’d have to work out a longer-term agreement that would cost districts money.

“The goal isn’t ‘Geez, let’s have something awful happen so that people think that virtual education is a great option,’” Durand said. “But I do think … one outcome of this could be more people are aware of what we can do.” And if districts take K12 up on its services and are satisfied with them, “maybe they’ll want to continue with us in some form.”

Other ed tech players are taking steps to make their tools more accessible, but at no cost. The company behind the popular online quiz site BrainPOP is offering free use of its tools to schools closed due to the virus. Outschool, an online learning program that’s often used for home-schooling, is offering free teacher training about how to hold classes online by video. And Khan Academy, a nonprofit that offers free online lessons and quizzes, is drafting a page aimed at helping new users get started if they are facing school closures.

Research has generally shown that instruction delivered online is much less effective relative to in-person learning. There are few studies on virtual instruction in the wake of school closures, though. Other research has found that students don’t suffer much academically from occasional snow days, but they do post lower test scores after longer spells of closed school.

Doug Levin, an educational technology consultant who was previously the executive director of the State Educational Technology Directors Association, said that companies are likely to use the coronavirus outbreak to hawk their products, both because district administrators may feel pressure to prepare and because new money may be available.

“Marketing executives in ed tech companies are anxious to get the attention of school district administrators, particularly in a time of crisis,” he said. “That is something we have seen in the response to school safety concerns around in-school shootings.”

Levin said additional challenges to widespread remote learning include students who have responsibilities at home, like caring for younger siblings, and school districts that lack the infrastructure to effectively deliver instruction.

“If they have not already laid the groundwork to deliver courses online, the notion that they could outsource that — it’s fanciful,” he said. “To do it well, this is something that takes a good deal of time and training.”

Levin also warned school districts against making big purchases in response to potential closures. “Would I spend a lot of money and buy new technology and invest millions of dollars on a solution that the odds are very high I would never use?” he said. “That’s not how you would responsibly spend your money.”

Even charter networks where schools already have a lot of technology available for students, and the infrastructure to support it, are not quite ready.

Stefanie Gilary, a spokeswoman for DSST, a large charter network in Denver, said the organization is still looking at options.

“Since we have 1-to-1 technology we definitely feel really lucky,” Gilary said, referring to the fact that all the school’s students have access to a portable tech device. “It will give us some opportunities for remote learning, but we are still exploring what that would look like.”

Since some families don’t have internet access at home, Gilary said DSST is considering relying more on applications on cell phones, which more students have access to.

Mike Miles, the CEO of the Academy of Advanced Learning in Aurora, said his network Third Future Schools, which includes two other schools in the southern part of the state, never closes schools — even for snow days. The group was already in the process of putting teacher lessons online, but that work may not be done before the summer.

“Frankly we’re behind when it comes to preparing for a pandemic, but hopefully we can get up to speed,” Miles said.

Miles said not all his students have internet at home, or laptops, so the decision to close and switch to remote learning would not be made lightly.

“There’s no pressure on us right now to stay open or to close, but we put pressure on ourselves,” Miles said. “We never close. We understand that parents still have to work and there has to be a safe place for students.”

Other schools that are also a step ahead are those that use e-learning days — days where schools are closed, but students are doing classwork from home.

Twelve states have formal policies on “e-learning days” to count virtual instruction toward attendance and academic requirements.

In Colorado, a handful of schools have begun using virtual instruction days in place of snow days. One is a high school in District 49, in the Colorado Springs area, south of Denver.

A spokesman said the school uses a virtual instruction model for those snow days, and called it “an advantage” for the district, which is now looking at whether it could expand it districtwide in case schools needed to shut down.

For remote-learning days, Colorado requires districts to “ensure that all students have the appropriate electronic equipment and resources,” including hardware and internet access.

In Indiana, many schools — particularly in suburban districts — regularly hold e-learning days instead of canceling classes for snow or professional development. Remote learning has grown so common that schools no longer need to seek permission from the state to use an e-learning day in place of a regular school day.

But e-learning is not the norm for Indianapolis districts that serve mostly students from low-income families. Wayne Township on the west side of Indianapolis, for example, hasn’t yet held a districtwide e-learning day for its 17,000 students, 70% of whom come from low-income families.

Similarly, it’s unclear whether the Detroit Public Schools Community District, or the many charters that operate in the city, could provide remote learning to students. In 2017, just 67.5% of households in the city had broadband internet, the lowest rate among 25 large U.S. cities.

Likewise, in Memphis only about 72% of households have internet access at home.

In 2018, school officials there had to quickly provide laptops and put together a remote instruction plan after a rat infestation forced Shelby County Schools to relocate 800 students from Kirby High School for four months. But plans for students to use libraries or community centers to connect to the internet would not work during a coronavirus outbreak since health officials say people should avoid public gathering places.

In Washington, where some schools are already closing for a few days, education officials issued a memo advising that, “it will likely make more sense to cancel school and/or district services and make up missed days at the end of the school year, rather than deploying a distance learning model that can be accessed by some, but not all, of your students.”

In Hong Kong, officials encouraged schools to use online learning for 800,000 students who have been out of school for a month due to coronavirus concerns, the Wall Street Journal reports.

Teachers there have tried a variety of approaches, but some parents reported difficulty helping their children with their homework or keeping them on task, the paper reported.

The ed tech-focused news outlet EdSurge interviewed several teachers from private international schools that have been closed for long stretches in China, and more recently in South Korea. At first, teachers emailed students work. Then as the closure dragged on, schools started offering instructional videos, or audio to accompany a lesson. Some teachers struggled under the longer work hours as they tried to check in with each of their students.

One Chinese teacher noted that some students were struggling, especially those in younger grades or those who didn’t have as much support from family members.

“Students are bored; students are lonely,” the teacher said. “We have students who are just completely absent.”

In many cases, school districts will ultimately make school closure decisions with local health department officials.

Heidi Dragoo, epidemiology program manager for a Colorado mountain community that closed an entire district last fall over a widespread stomach illness, said communication is one of the most important things.

“The earlier you can get out and reach out to your partners the better,” Dragoo said. “It took everyone working together.”

Chalkbeat journalists Kalyn Belsha in Chicago; Matt Barnum, Alex Zimmerman and Amy Zimmer in New York; Laura Faith Kebede in Memphis; Lori Higgins in Detroit; and Stephanie Wang in Indianapolis contributed to this report.