Many schools across Japan reopened Monday after a summer vacation that was shortened to allow students to catch up on classes missed due to earlier closures caused by the coronavirus pandemic.

The shortest break decided on by municipal authorities was only nine days. Usually, Japanese students take more than a month's summer vacation.

Masked students arrive at their elementary school in Ogaki in Gifu Prefecture, central Japan, on Aug. 17, 2020, as a new school term starts the same day following summer holidays that were shorter than usual to allow students to catch up with schoolwork they missed during closures caused by the new coronavirus outbreak. (Kyodo)

Students wearing face masks started arriving at Ushioda Elementary School in Yokohama, near Tokyo, around 8 a.m. Their summer vacation had been shortened by roughly half.

"I was unable to go enjoy myself at the swimming pool because of the coronavirus," said Naoya Hirasawa, 12.

Schools are required to take steps to reduce the risk of heat exhaustion as well as prevent coronavirus infections. Temperatures have risen rapidly in recent days, with the mercury hitting 35 C or above in many locations.

In the central Japan city of Nagoya, students at Shimizu Elementary School sat in chairs placed apart and attended school assembly in their classrooms to avoid crowding, with the principal, Tomio Suzuki, addressing them through the school public announcement system.

"Let's do our best to be able to say that we all made it through 2020, despite the novel coronavirus and the heat," he said.

In classrooms, windows were left open for ventilation while air conditioning was also running. A teacher told pupils that to prevent heat exhaustion, they can take off their masks as long as they maintain social distancing.

Photo taken Aug. 17, 2020, shows a bottle of disinfectant in a classroom of an elementary school in Ogaki in Gifu Prefecture, central Japan. (Kyodo) 

Sone Elementary School in Takasago, Hyogo Prefecture, only had a nine-day vacation. "I didn't get much summer vacation, but I am happy to see my friends," said 11-year-old Suzaku Fujiwara.

Of the 1,794 local education boards across the country that closed elementary, middle and high schools due to the pandemic, 1,710 boards said as of June 23 that they were planning to shorten summer vacations, according to the education ministry.

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