Kelly Hester wanted to know: Was there something her students had been hearing a lot about lately?

“Maybe on the news, or on Facebook?” Hester asked her ninth- and 10th-grade science class one afternoon last week. “What is one thing you have seen just everywhere?”

The teenagers at T.C. Williams High School in Northern Virginia needed no more clues. From all corners of the room came the same word — muttered, shouted or stated flatly — “coronavirus.”

Hester nodded. She made several promises: By lesson’s end, she said, her students would understand the difference between an epidemic and a pandemic. They would know whether a virus is alive (it’s not). They would leave class less scared of the coronavirus, she vowed, and better equipped to fight its spread.

“We are going to learn about the coronavirus so we can be prepared,” Hester said. “The best way to prepare is to educate people.”

It’s a challenge confronting teachers across the nation as the flu-like illness, which originated in China at the end of last year, veers rapidly toward pandemic status. This week, infections soared to more than 113,000 in more than 100 countries, and deaths climbed to about 4,000 worldwide.

The virus is infecting America, too: More than 600 cases of the disease have been reported in the United States, in more than 30 states and the District, with 22 deaths.

“Coronavirus is dominating classroom discussions,” said Jaclyn Reeves-Pepin, executive director of the National Association of Biology Teachers. “And there hasn’t been a lot of good information, especially online, so we’re all just kind of playing catch up.”

Rampant false information — for example, exaggerated estimates of the virus’s mortality rate or advertisements for fake cures — has ricocheted across the Internet in recent weeks, fueling anxiety. The phenomenon is especially pronounced among young people, said Ingrid Katz, a Harvard Medical School assistant professor who studies infectious diseases, because teens tend to glean their news from social media platforms.

This leaves educators in a delicate position, Katz said. Teachers need to broach the coronavirus in class, she said — it’s an important opportunity to ensure students know basic facts about the virus, as well as where they can seek up-to-date, accurate information (key sources include the CDC and the World Health Organization).

It’s also a good chance for teachers to explain recommended methods to prevent infection, Katz said: frequent handwashing, staying home when sick and trying not to touch one’s face in public.

“But,” she said, “we really need to be sure we’re not scaring them.”

A desire to assuage students’ fears is partly what led Hester to offer a class devoted to the coronavirus. She began working with fellow biology teachers to develop a lesson plan about two weeks ago, she said, shortly after federal health officials warned of the virus’s “inevitable” spread in the United States.

Hester, 28, said her students started discussing the coronavirus about the same time. Their worries surfaced in pre-class chitchat, she said, and in uncomfortable jokes: If someone sneezed, a peer might reply, “Oh no, the coronavirus!”

Others lingered after class to confide their fears. Sidling up to her desk, they waited until other students left before asking, “Is the coronavirus coming to America soon?” “How bad is it going to get?” And, again and again: “How worried should I be?”

“A lot of them were convinced that, if they did get it, it was going to be a death sentence,” Hester said.

To kick-start class last week, Hester posed her own question: “Most people who get the coronavirus will die,” she said. “True or false?” Seventeen of her 22 students replied “True” — and broke into relieved giggles when they discovered their error.

Minutes later, Hester distributed a worksheet filled with short-answer questions and pictures of disease-ridden globes, each dotted with small orange circles to represent infection.

Eighteen-year-old Carlos Garcia bent over his paper to scribble the definition of “virus” in an empty box. “It transforms good cells,” he wrote, nose almost touching the desk, “to bad ones.”

A few seats away, Maria Gonzalez, 18, explained to a wide-eyed classmate that the term “pandemic” refers to an illness that has traveled everywhere. She flung her arms wide, then pressed her fingertips and palms together to form a small circle.

An epidemic tends to stay in a smaller area, she said. “This one didn’t.”

In three years teaching at T.C. Williams, Hester said, she has never seen students so invested. After one lesson on the coronavirus, teens arrived the next day asking to learn more about ­viruses — “just complete engagement, what every teacher dreams of,” she said.

The coronavirus affords a perfect opportunity to get students excited about science, said Christine Royce, former president of the National Science Teaching Association. Educators can use the outbreak to introduce topics such as how viruses spread in the human body and why antibiotics are useless against them, she said — though it’s important to tailor classes to different age levels.

While high school students can absorb complex information such as disease transmission at the cellular level, middle school teachers are better off exploring why scientists do not classify viruses as living things, Royce said. Elementary school educators should focus on prophylactic measures — reminding children to cough into their elbows or to continue washing their hands for the duration of singing the “Happy Birthday” song twice.

Royce’s association published lesson plans along these lines on its website about a week ago. So far, she said, the guidelines have garnered nearly 7,000 views from teachers throughout the country — and readers’ average time on the page is a minute longer than is typical.

Royce recommends avoiding one topic at all ages.

“I would not focus on the number of deaths,” she said. “Just use that as a springboard for talking about why we need science: to prevent those things from happening.”

Down the hallway from Hester, history teacher Gabriel Elias, who also instructs ninth- and 10th-graders at T.C. Williams, is not shying from the death toll. But he makes sure to keep it in perspective.

Elias has asked his students to create a presentation comparing the coronavirus with four major outbreaks in human history: the Plague of Justinian, the Black Death, the smallpox pandemic of the 16th century and the 1918 Spanish flu. Scholars estimate each illness killed millions around the globe.

“They look at the actual numbers and they see, okay, coronavirus is bad,” Elias said. “But it’s not so bad.”

As part of the same project, students must ponder the social, economic and political effects of disease. A sample poster, displayed for students’ benefit in Elias’s third-floor classroom, notes that the Black Death caused people to “blame Jews,” and the Spanish flu led some to “blame [the] Spanish,” while the coronavirus is making people “blame Asians.”

This part of the lesson, Elias said, feels personal. In the days after the coronavirus began dominating headlines in the United States, he noticed some students picking on peers of Asian heritage — insisting they carried the coronavirus, or pretending to shrink from their touch.

“So I tell them how it was historically inaccurate and harmful toward the groups that got blamed,” Elias said. “I want them to be better human beings.”

Elias launched his coronavirus courses about a week ago, he said, so it is too soon to tell whether they will reduce anti-Asian taunts. He is also unsure whether students find it calming to compare death tallies, although early reactions are promising.

During class last week, one effect was immediate.

Elias began the afternoon with an online quiz asking whether pandemics change how people view their government or their religion. Grabbing a rose-gold karaoke microphone, Elias put the query in relatable terms: Could the coronavirus, he asked, alter teens’ opinion of U.S. officials, or of God?

At first, the room rang with “No”s. Many students insisted their Christian faith, in particular, was unshakable.

Elias motioned to the history, the heavy statistics, hung on the walls. He asked again.

When the responses rolled in to an online form, 42 percent of the class had selected “Maybe.”