At a little past 2 p.m. on a recent day, pupils exited the Shinjuku Ward-run Yotsuya Elementary School in Tokyo under the hot sun, cheerfully saying goodbye to their peers and teachers.

The temperature reached 36.4 degrees in the heart of Tokyo that day on June 30, setting a record high for June.

Most kids were wearing caps, with some seen holding parasols and taking off their masks.

"We tell them it is OK to use parasols, ice packs, cooling towels and other items," said Principal Masahiro Ishii.

The grade school encompasses a wide school district, and some students have to walk nearly 30 minutes to commute.

Because it is difficult for adults to keep an eye on children at all times, they make sure anti-heatstroke measures are taken, including encouraging students to hydrate themselves before leaving school for home.

ENSURING STUDENT SAFETY DURING HEAT WAVE

With Japan experiencing a streak of unusually hot days even before the summer vacation, school officials nationwide are struggling to protect children from heatstroke, particularly with many reluctant to remove their masks. 

Officials are especially worried about the safety of children while going to and from school because it is difficult for adults to keep an eye on them.

While parents and guardians voice concerns, experts say it is risky for kids on their way home when it gets particularly hot in the afternoon and call for stepped-up measures.

According to the education ministry, air conditioners have been installed at schools at an increasing pace in recent years.

As of September 2020, the installation rate of air conditioners in regular classrooms at public elementary and junior high schools across the country was 93 percent.

Meanwhile, outdoor activities such as physical education classes and going to and from school continue to pose high risks.

In its guidelines released in 2021, the ministry called on schools to instruct children to wear cool clothing, don hats or caps and properly hydrate themselves to prevent heatstroke when going to and from school.

The guidelines also encourage school officials to actively call out to children to remove their masks when enough distance is maintained with others.

Schools and municipalities have introduced anti-heatstroke measures.

In Kumagaya, Saitama Prefecture, which is notorious for high summer temperatures, the municipal government recommends students of 45 city-run elementary and junior high schools to use umbrellas on their way to and from school.

While umbrellas shield pupils from sunlight, they have their own advantage because they also can help maintain social distancing.

The municipality plans to distribute sun umbrellas to all of about 9,000 students by the end of the year, officials said.

Similar efforts are also taken in Mibu in Tochigi Prefecture and Toyota in Aichi Prefecture.

MASK WEARING INGRAINED IN CHILDREN

However, it is not easy for school officials to have children remove their masks.

"We urge them to take them off," a principal of a ward-run elementary school in Tokyo said, adding, "With mask wearing becoming a habit, some children are reluctant to remove their masks in front of other people."

The principal said school officials try to reason with pupils, saying that they understand their feelings and telling them that wearing a mask makes it hard to breathe.

But they said they can't force children to take off their masks.

Meanwhile, parents and guardians are feeling anxious.

A woman in her 30s living in Aichi Prefecture said her second-oldest daughter, who is a second-grader, complained of a headache soon after she came home one day in June.

Her face was red and her back was soaked with sweat.

Her daughter said she walked more than 30 minutes to get to her home, which is located on a hill about two kilometers from the school, wearing a mask along the way.

The school instructs children to take off their masks outdoors only when there are no other people around. Her daughter seemed to have assumed she couldn't take hers off because pupils return home in groups.

"Children can't respond flexibly. I'm worried every day," the woman said.

A second-grade boy living in Tokyo is hesitant to take off his mask because he is afraid of being harassed by other children.

"Some children act like 'mask police' over the past two years of the novel coronavirus pandemic. I want teachers to strongly instruct them to remove (their masks)," said his 40-something mother, referring to vigilante-minded people who criticize the unmasked.

A man in his 30s living in Saitama Prefecture said his fifth-grade son hardly takes his mask off even in hot temperatures, saying he didn't want to stick out among his friends.

The man thinks that his son is mired in the idea that wearing a mask is a must.

Masuji Hattori, a special guest professor at Hyogo Medical University, warns of the risk of heatstroke during school-commuting hours.

"It gets hot and the sunlight becomes particularly intense when children leave school for home," he said. "I want school officials to instruct them to drink liquids before going home. Using an umbrella is also effective."

The expert recommends pupils remove their masks when they go to and from school, saying, "When you wear a mask, it becomes difficult to notice that your mouth is dry and you could end up being dehydrated."

But in light of a resurgence in new COVID-19 cases, the professor calls on school officials to make sure children remain quiet on their way home.

Heatstroke cases apparently due to exercising outdoors at schools have been reported in recent months.

In June, 22 students of a city-run junior high school in Hyogo Prefecture were rushed to a hospital when they were practicing for an athletic meet.

"Not only the temperature but also the humidity must be taken into consideration to make decisions in a flexible manner, including whether to cancel outdoor exercises depending on the situation," Hattori said.

(This article was written by Aya Shioiri, Nobuaki Tanaka and Yukihito Takahama.)