Al Horford never expected to become a live-in physical education teacher for his three children -- especially for the oldest, Ean, his 5-year-old son. But when the COVID-19 hiatus and accompanying self-isolation hit the United States, the Horfords found themselves together in an apartment in the Philadelphia area without a yard.

There are parks nearby, but on rainy and cold days, the Horfords invent ways to keep Ean and his 3-year-old sister, Alía, active and engaged. Horford has become a master designer of indoor obstacle courses, and he times both Ean and Alía. "They get really into it," Horford said. "Ean loves trying to break his own records."

The family couch breaks apart, and Horford sometimes uses the pieces as obstacles to run around. Some courses include stations for 20- or 30-piece puzzles. Others are almost household versions of the NBA's Skills Challenge at All-Star Weekend. Ean will have to score a soccer goal before advancing, pick up toys stationed around the apartment and drop them into buckets elsewhere, or even execute a few pushups.

"We are getting pretty creative," Horford said, laughing.

Kids in Ean's age range -- between 4 and 6 or 7 -- represent a unique parenting challenge during self-isolation. They are old enough to understand something is wrong -- that their lives have been disrupted -- but not the level of seriousness, or how long the disruption might last. At the same time, many of them are not old enough to have intensive school assignments to routinize long portions of their days -- or to play immersive video games that knock hours off the schedule.

In normal times, NBA players and coaches travel more than almost anyone. They keep strange hours. They are not used to full-time, heavy-lifting parenting outside the offseason -- let alone parenting kids in this age range during a period of strict isolation.

"You gain a whole new respect for stay-at-home moms, nannies and teachers," said Gordon Hayward. Hayward and his wife, Robyn, have three daughters, including Bernie, who is 4.

"It's like every five minutes, I'm trying to think of something for them to do," said Rudy Gay, who has two sons -- Clinton, 5, and 4-year-old Dean. Gay got excited when they found a box turtle -- they quickly named it Squirtle -- in the backyard on Wednesday, thinking it might hold their interest for hours. "It was cool for three minutes," Gay said. "Then they wanted something else."

Players and coaches say they have tried to be honest with kids around that age about the virus, without frightening them. "We tell them there are a lot of people who are sick, and that we can help them by staying home," said Kyle Korver, who has three kids -- including his son Knox, who is 5. Gay uses the word "germs" instead of "virus," he said.

As the Horfords gathered to watch a movie during the first week of self-isolation, Ean suddenly blurted out, "'The reason we can't go anywhere is because of the coronavirus,''' Horford said. "I was surprised. When you think they aren't listening, they are. So we talked about it. I didn't want to freak him out or make him anxious."

Thaddeus Young's 6-year-old son, Taylor, is a question machine, Young said: "It's all day, every day: 'How long do we have to stay at home? Why this? Why that? What is the coronavirus?'"

Kids ask often about school, or when they can see friends. "That's the hard part," said Cleveland Cavaliers coach J.B. Bickerstaff, who has three kids, including his 6-year-old son, Blade, the youngest. "That's what [Blade] doesn't really understand: 'My friends are healthy. I'm healthy. Why can't we play? Why can't they come over?'"

Gay said his kids seem to enjoy being home from school. "I don't know if that's good or bad," he chuckled.

Blade does schoolwork every morning, Bickerstaff said. JJ Redick and his wife, Chelsea, begin the day with a morning meeting for their two sons -- Knox, 5, and 3-year-old Kai. Both then break off into age-appropriate educational activities. In the middle of the day, Redick's sister-in-law, Kylee Kilgore, who is staying with the Redicks, holds a geography or science lesson; a recent one centered on planets, Redick said.

The Redicks have introduced a "word of the week" -- the latest one is "flexibility" -- that they discuss throughout the week. Redick is helping Knox and Kai write and illustrate short books about two tiger cubs, named Elijah and Ethan, that are based on Knox and Kai and have various adventures. The one they are working on now has the tigers in New Orleans, where Redick plays for the Pelicans.

Redick himself was homeschooled by his mother, Jeanie, through fifth grade. "I have a newfound respect for my mom and her teaching ability," he said. "We thought we might use this time to learn a new language or something. Instead, we are trying to get to the end of every day, have a glass of wine, and go to sleep."

(Redick's younger son, Kai, has developed a funny habit of attributing all acts of hygiene to COVID-19-related vigilance. "'We're doing this because of the coronavirus!'" he might shout during some, umm, routine bathroom maintenance, Redick said. "And we're like, 'No, we're wiping your butt because there is poop on it.'")

Korver and his wife, Juliet, have tried to schedule school activities for their kids -- Kyra, 7, Knox, 5, and Koen, 3 -- from about 9 to 11 a.m. on weekdays, Korver said. Knox is fascinated with sharks. Each day, the family picks a photo of a shark from one of their many shark-themed books. Korver sets a five-minute timer, and each member of the family draws a picture based on the photo. "Then we talk about what we drew," Korver said. They might repeat that a few times, and discuss different types of sharks.

Young's wife, Shekinah, prints out worksheets for Taylor and 9-year-old Thaddeus Jr. "I'm learning she's the tough one," Young said. "She makes them do certain things I might not make them do. I'm learning a lot about how my household works when I'm gone." (Interestingly, Young has contemplated homeschooling his two sons instead of enrolling them in new school after new school as he moves around the NBA on short-term contracts, he said.)

Kids notice their fathers are home much more. Before this pandemic, Bickerstaff's kids would almost always call for Bickerstaff's wife, Nikki, when they needed help -- even when Bickerstaff was home -- because they are more used to her presence. "It's usually, 'Mommy, Mommy!'" Bickerstaff said. "But I can already see it becoming more balanced now."

Gay has been doing some grocery shopping, and he said his kids worry he is going on a road trip every time he gets in the car.

On the flipside, Hayward's oldest daughters -- Bernie and 3-year-old Charlie -- miss going to games at TD Garden. "This was the first season they actually liked to go," Hayward said. "And not to watch me play. Just to hang out. They miss that."

Recreation time is big. Bickerstaff holds "physical education" in the afternoon in their yard, he said. Korver is renting a house in Milwaukee with a tiny backyard, so a lot of physical activity happens in the basement, he said. They play soccer, tennis, even baseball. "I am worried we are going to poke a hole in the drywall," Korver said. "The ceiling is pretty low too -- I have to really watch my head."

(If he damages the walls, another NBA figure will be billing him. Korver is renting the home of Taylor Jenkins, the Memphis Grizzlies' coach, who spent one season as an assistant in Milwaukee.)

The San Antonio Spurs helped Gay outfit his garage with weights and exercise equipment, and his two sons like to "work out" with him, Gay said. He has them do jumping jacks and other exercises as he does the serious stuff -- "to try to get them tired," Gay said. "Their level of focus isn't quite where mine needs to be," Gay laughed. "There are times where I am doing pushups and suddenly they are both on my back."

Steve Hetzel, an assistant coach with the Orlando Magic, has (among many other things) mimicked the old American Gladiators Powerball game in his living room with his three children: Aden, 10, Selah, 5, and Jackie, 4. Hetzel stands in front of a basket holding a blocking pad as a shield, while each child tries to scoot past him and plop a ball into the basket.

Hayward is a gamer, and he has introduced Bernie and Charlie to Mario Kart and Pokemon-themed games. (For the record, Hayward usually plays as Bowser in Mario Kart because he likes to knock other players over.) Horford has a mini Fisher-Price hoop in his house, and Ean now wants Horford to play hard defense against him, he said. The Korvers are into UNO Flip!

No one is skimping on screen time. "I think I've watched 'Frozen' 35 times already," Hayward said. Young has a home theater at his Chicago residence, and his two sons will disappear there for hours, he said. "Once [Taylor] gets bored, he'll just say, 'I'm bored' and go," Young said. "And that's all she wrote."

Bickerstaff's son, Blade, plays a healthy amount of NBA 2K. "A friend made the settings pretty easy, so he can drop 40 on anyone," Bickerstaff said.

Eating routines are subject to change. "[Ean] snacks the whole day," Horford said, laughing. "He's just eating all the time."

Everyone is trying to look on the bright side: This is an opportunity to spend more time with their kids, and see them in a different light -- adapting to a challenging circumstance.

"It's just good," Korver said, "to be together."