Pheng Lim knows how exhausting virtual school can be for children.

As principal of Folk-Arts Cultural Treasures Charter School in Philadelphia, Lim and her team have prioritized balancing lessons with not overwhelming their K-8 students with large chunks of time in front of a computer. Kids have breaks between every class and an hour for lunch. Teachers remind students to shut off their screens, to move around, to pace themselves, to engage in hands-on activities.

But Lim is also the mother of two FACTS students, and while her 9-year-old manages virtual school well, her first grader can get overwhelmed.

“My 6-year-old just has had a more difficult time,” said Lim. “After two hours, she is done, and she comes to me for hugs and encouragement.”

With COVID-19 forcing schools to conduct most or all of their learning via computer, the amount of time children spend on screens has risen dramatically, with mixed results. Some children are coping fine, but others are dealing with fatigue, headaches, and strain in a way they didn’t when classes were face-to-face.

Some schools, like FACTS, de-emphasized screen time from the beginning of the term.

But other districts have adjusted their plans to lessen students’ screen time. Philadelphia and Cherry Hill School Districts in recent weeks adjusted the amount of time students spend in front of computers.

Cherry Hill elementary students used to have instruction from 9 a.m. to 3:30 p.m., with 50 minutes for lunch and breaks built in. After concerns were raised, the district shifted gears, and elementary students now have instruction from 9 a.m. to 1 p.m.

The shift, Superintendent Joseph Meloche said in an email to families, “addresses common concerns expressed by parents, teachers, and community members: the amount of daily screen time, length of the academic day, lunch time with friends, parent contact time, and student fatigue. We anticipate that a shift in the remote learning schedule will allow for a smoother transition to the hybrid learning model, which will begin on Nov. 9.”

Philadelphia dropped kindergartners' school day to two hours, adding time for a screen break and 20 minutes of movement.

"Even with the breaks that are already in — the amount of time in front of a screen is just too much,” said Superintendent William Hite Jr.

» READ MORE: Some Philly students may not be allowed to return to class this school year, Hite says

Kindergarten ought to be full day, said Nyshawana Francis-Thompson, executive director of Philadelphia’s office of curriculum and instruction, but the district needed to balance academic needs with what’s developmentally appropriate for young children.

“As a large urban school district, we recognize that most of our students get their supports from their teachers, and unfortunately, their teachers are on a screen,” she said.

FACTS knew it would be fully digital for at least the first stretch of the school year, and Lim said many planning conversations were focused on how to teach the concepts the school’s 500 K-5 students need to learn while not overwhelming them.

“Our kids' eyes can’t be on screen all day long,” said Lim. “We know that live sessions can be more engaging, but once they have that fatigue, are we really reaching them at all?”

FACTS has discovered that varying the kinds of screen time helps. Academics are important, but so is time for more informal small group discussions.

When Mia Victor, a third grader at Gladwyne Elementary, was learning remotely only, it was tough, said her mother, Courtney Victor. Mia’s teacher was careful to implement screen-free time in the virtual part of the school day, and Mia wears blue-light glasses to ward off possible eyestrain during hours spent in front of her laptop.

“But she seemed so tired, she kept saying that her eyes were tired,” said Victor. “It’s exhausting to look at a screen for that long for anyone, let alone for a 9-year-old.”

» READ MORE: Cyber charter enrollments are surging. School districts are picking up the tab.

Things have improved for Mia now that Lower Merion schools have moved to a hybrid model. Mia learns at home in the mornings, and spends afternoons in her classroom.

Prior to COVID-19, Mia and her brother, who attends a private kindergarten in person, didn’t have their own iPads. Now they do, but Victor feels she needs to be vigilant.

“It’s a lot of monitoring, something I really have to keep on top of,” said Victor.

Parents should not feel guilty about the additional screen time, said Michael Robb, senior director of research for Common Sense, a nonprofit that studies the effects of technology on young people. There’s a difference between time spent playing video games or scrolling through social media and time spent in Zoom meetings with teachers and classmates.

Still, Robb said, “it is challenging to do remote school where kids aren’t necessarily suited to be learning for long periods of time online,” he said. “You have to balance that with the fact that kids have academic responsibilities that need to be taken care of.”

» READ MORE: Bridging the digital divide for the ‘have’ and ‘have nots’: How schools are meeting the need during remote learning

For some students, the balance has been miserable.

Dorothy Schwab, a high school freshman, spent their first month of school at Academy at Palumbo, a Philadelphia magnet school. They spent seven hours online, with a course schedule that mimicked what they would have experienced in person.

Despite being a strong student, they were miserable. It was too much.

“Classes all day just didn’t work out,” said Schwab, 13. “It was tiring and stressful; it was incredibly hard to look at a screen all day.”

As a first-year high school student, virtual school felt especially isolating, they said. Schwab recently left Palumbo and enrolled in a cyber charter school, where the work is online but spaced out.

“The classes aren’t all in a line, and when you are online, you’re moving through a lesson and doing the work with a teacher,” they said.

Molly Maldonado has no problem telling her son’s teacher when the boy, a first grader at a Philadelphia charter school, is overwhelmed, deciding what assignments are must-dos and which are OK to skip in favor of going outside to play or do a hands-on science experiment.

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Maldonado, a teacher herself, is frustrated with the expectations many schools have for children these days.

“I hear these complaints from teachers and parents, ‘Oh, my kid won’t sit still,' but they’re being normal kids, and we’re asking them to do something that is scientifically not appropriate for their development,” said Maldonado.

And while she’s comfortable advocating for her child, she knows that many parents feel as if they need to have their kids finish a long list of work online, or else.

“Some days, my son does really well and he’s there all day and learns all the things, and some days, I say, ‘OK, you’re having a meltdown,' so I take him out early and have him do something else,” she said. “He loves learning, and my goal is not to kill that this year.”

Cherry Hill’s reduction in screen time has helped Danielle Ricci’s youngest two, students at Johnson Elementary.

“They were toast by midafternoon, and it was just so hard to reengage them after breaks and independent time," said Ricci. The 9 a.m.-1 p.m. schedule with just one break has been better for the kids. But her older two, middle schoolers, haven’t benefitted much from the shortened day, she said, and seem more bored.

» READ MORE: How remote learning could worsen undetected vision problems in some kids

In Philadelphia, third-grade teacher Meg McGettigan sees it every day: “The life is gone out of the class by 2 p.m.,” she said. “They’re begging for no homework, they’re begging for no more screen time.”

Complicating the time spent in front of a computer are the distractions at home, a situation that’s magnified for many students in Philadelphia, where McGettigan teaches at Meade Elementary. Many are managing school solo; one of McGettigan’s students learns from the break room of his mother’s job, another recently fed his infant sibling while juggling a lesson.

“The distractions are huge,” said McGettigan.

Teachers like McGettigan are getting creative to keep students engaged. Her 16 students are thrilled to have show-and-tell, where they practice their oral communications skills and get to know their peers better.

Even the 11th and 12th graders Angela Crawford teaches at Martin Luther King High School in Philadelphia get antsy when there’s too much screen time.

If a lesson is long, she’ll tell them go drink water or get fresh air, then come back.

“Personally, I make some professional judgments,” said Crawford, who teaches English. “I have to do what’s good for kids. I really try not to teach for long stretches of time. We’ll do a warm-up, I’ll teach, then they’ll go off-line and do work. We’re really asking a lot of them.”