Anita Tandon and Sujit Chakravarthy, parents of three young children, ages 3 months to 7 years old, have taken extreme measures to keep order in their home during quarantine.

“At 9 o’clock, school’s in session and I stop being ‘Mommy,’” said Ms. Tandon, who runs a marketing advisory firm in Burlingame, Calif. “They have to call me ‘Teacher Anita.’ They can’t just goof off like they can with Mom and Dad.”

There are worksheets, activities, Khan Academy online courses and writing games. Around 5 p.m., Teacher Anita retires to work. Mr. Chakravarthy takes over, springing out of his home office ready for P.E. He goes by Coach Chakravarthy.

“It’s Day 3 of God knows how many,” Ms. Tandon said wearily.

It has been just over a week since Americans started to be ordered to stay at home and out of the way of the coronavirus pandemic. For many people, it already feels like an eternity.

Kids are trying to escape. Careers are falling apart as parents working from home become de facto kindergarten teachers. Marriages are being strained. Couples who wanted to break up are stuck together; Craigslist roommates are suddenly family. And everyone has to stay put with others 24 hours a day, seven days a week, because there is nowhere else, really, to go.

For many people, it is hard to complain: If they can stay home as a unit and their work allows them to make a kitchen counter into an office, they are the lucky ones.

But cabin fever is setting in. Families are going slightly mad — and getting mad at one another.

On Twitter, some people cracked jokes about selling their children. Some were even tired of seeing so much of their pets. Gov. Andrew M. Cuomo of New York said on Sunday: “I live alone. I’m even getting annoyed with the dog, being in one place.”

The stir craziness is likely to be just beginning. By the end of last week, at least one in five Americans was under orders to shelter at home, with more states following this week. It’s unclear how long these restrictions will last. Schools might not open again until the fall.

“There’s going to be increased misbehavior, defiance, tantrums and blowing up,” said Jennifer Johnston-Jones, a child psychologist in Los Angeles. “After a natural disaster, you go back to normal. With this, there’s not going to be a back to normal.”

Sabrina Benassaya, a privacy specialist in Menlo Park, Calif., has four children between the ages of 2 and 10, whose school and day care have been canceled.

“It’s hard. I cannot lie,” she said. To survive, she had David Magidson, a clown who performs under the name Boswick, give a birthday show last week for the kids via FaceTime.

The Benassayas have a house and a backyard. To quarantine in a home like that is a privilege that many American families do not have, Ms. Benassaya acknowledged. “We are so lucky,” she said.

Family coaches are offering tips to help get through this.

“One of the messages I’ve been trying to push to parents is there’s only the two of you,” said Maryellen P. Mullin, a family therapist in San Francisco. “There’s nowhere to go out, and no one can come in.”

Her schedule has been so full that she is starting to offer a new workshop for $20 called “My Kids Are Home, I Need Help.”

Escapism seems key. Katie Jacobs Stanton, a mother of three and the founder of Moxxie Ventures, a start-up investment firm in San Francisco, dressed as if for a prom one day. Another day, the whole family wore onesies.

“Last night, we came to dinner and pretended we were someone else in the family. It was really funny until my son did his impression of me,” Ms. Stanton said. “I’m no longer paying for his college education.”

Her friend Aileen Lee, who is also a venture capitalist, has been posting photos of her husband in different costumes every day. One day he dressed as a mermaid, with a red wig and shiny sequined skirt.

Working moms confront battles they thought were over

The burden of handling coronavirus quarantine in many homes was falling on moms, families said, with much of the new tension in couples caused by fights over what women thought were battles that had already been won.

When Lea Geller, a novelist, blogger and mother of five in Riverdale, N.Y., first thought about a quarantine, it seemed it could be fun.

“I thought it would be a week of snow days,” Ms. Geller said. “But now it’s lasting forever and ever.”

“To some degree, it feels like we’re running a WeWork,” she said. “My husband’s running tech support, running round with cables, and I’m just shoveling food into everyone’s mouths and loading and reloading the dishwasher a million times a day.”

Ms. Geller thought maybe she would have extra time with her husband, Mike Geller. But the only private time they have had was when they “literally hid” from their children in a back room the other day, she said.

“My new office mates are significantly more high maintenance,” Mr. Geller said, referring to the kids. He added that at least the tech support was now largely sorted and ready for Week 2 and more.

The hardest part is that Ms. Geller’s own work has gone on hold. When her husband’s office shut down, she gave him her home work space. Now she is having trouble thinking creatively in the 30-minute increments when she can sneak away from the family.

“There’s the constant certainty that someone is about to interrupt me and ask me for food or a stapler,” Ms. Geller said.

Maria Colacurcio, chief executive of Syndio, a human resources analytics company in Seattle and the mother of six children, said the lopsidedness was not a surprise. Even without a pandemic, domestic labor largely falls on women.

“So now where do you think the extra falls?” Ms. Colacurcio said.

Leah Wagner-Edelstein, director of an academic institute at University of California, Berkeley, and the mother of a 5-year-old and a 3-year-old who are now home all day, said she and her husband, Jason, had what she considered an equal arrangement.

“I still manage more or less our whole household, the cooking, most of the cleaning, the bulk of the home schooling,” she said. “Those gender divisions they just come out immediately.”

Toddlers need constant entertainment and can focus on only one thing for a few minutes. So Ms. Wagner-Edelstein got some younger cousins to sign up on a spreadsheet to help with entertaining her children every day. They can choose hand puppets, a dance party or name-that-color.

Teachers, she said, need to be paid much more.

Despite it all, Ms. Wagner-Edelstein said she was finding that her love for her husband was deeper. She is being gentler with him, and vice versa. They are focusing on small joys.

“We think of fun as big vacations,” she said. “But now maybe it’s just digging a hole in the front yard and finding what color the soil is.”

When adult children come home

Not all cabin fever families are dealing with toddlers. College students have been sent home, repopulating their parents’ empty nests. Other adult children, sometimes with friends and fiancés in tow, are turning their parents’ kitchens into co-working spaces.

But the reunions, at least initially, are careful. Many young adults said they were scared they could be taking the virus home to their parents, who may be more susceptible to the outbreak because older people are more at risk.

“All my Stanford friends and I are self-quarantining in our own rooms away from our families after getting booted off campus,” said Netta Wang, 22, a Stanford University senior who returned to her parents’ house in San Mateo, Calif. Her parents leave trays of food at her bedroom door.

Gillian Lurie, 20, had a great time on a study-abroad semester in Florence, Italy, but as coronavirus swept through that country, the program was shut down. Already on spring break, she traveled through Spain, Germany, Portugal and Ireland. This month, she came home.

“She managed to have a great time, but she brought home a souvenir,” her mother, Lisa Lurie, said. “A little something called the coronavirus.”

Now Lisa Lurie and her husband, Brian, who run Cancer Be Glammed, a lifestyle company that supports women coping with cancer, are quarantining their daughter in a back room of their Pittsburgh home. They communicate via FaceTime and drop meals at the door.

“The only thing keeping me sane is online mahjong,” Lisa Lurie said.

Other parents are setting up rules for their suddenly multigenerational households.

Haley Walker, 24, lives in Manhattan and works as a senior analyst for a commercial real estate company. For quarantine, she went back to her parents’ house in Williston, Vt., with her two sisters. Also in tow: one boyfriend and one fiancé.

When they all got to the four-bedroom house, they were thrilled and spread out. They set up mobile offices all around, commandeering the kitchen table and the living room.

Ms. Walker’s parents, Adele and Bob, did something that she said had never happened before: They called an emergency family meeting.

No more co-working and taking calls all day in the kitchen and living room, the young adults were told. Everyone was assigned a little work nook in a different part of the house. Also, there would be chores (vacuuming, dishes, trash, cooking dinner) and time slots for laundry.

“They love having us home and all together,” Haley Walker said. “But I think for my parents it’s both good and bad.”

Adele Walker said she was enjoying having everyone close. But “ask me how I’m feeling on Day 50 and my answer may be very different,” she said.