China's top education authority has launched a round of inspections across eight provincial-level regions in response to complaints made online in November that children in some primary and middle schools weren't being let out of the classroom in between periods — unless they needed to go to the toilet — to "ensure their safety".

The Ministry of Education has asked authorities at the local level to establish a supervision and inspection system to ensure students have breaks of 10 minutes between classes and that they are able to play outdoors during that time.

The ministry went further by suggesting local authorities organize surprise inspections on schools to make sure they are complying.

Schools in Beijing and the provinces of Hebei, Jilin, Zhejiang and Hainan have made rectifications, the ministry said.

The issue of break times came to light recently after a series of complaints by parents began to trend on social media. Topics about students barely having enough time to go to the toilet during break time provoked comments about the impact on their mental and physical health.

Local education authorities and schools must resolutely correct the practice of simply restricting necessary breaks and activities between classes in the name of "ensuring student safety", an official with the ministry said.

Schools have been asked to strengthen inspections on outdoor facilities and arrange for personnel to enhance campus safety.

Schools are also being encouraged to hold activities during 10-minute breaks.

Students at Cuiwei School — a high school affiliated with Renmin University — can take part in various activities during the 10-minute breaks between classes.

"We have lots of choices such as playing frisbee and bouncing balls in the playground," third-grade student Li Meizhou told China Central Television.

Physical education teacher Li Jukui said they are on duty in the playground and keep an eye on students during the break to help them solve any problems and ensure their safety.

"The break between classes is a good opportunity for children to be themselves. Although our campus is small and the space for outdoor activities is limited because of the buildings, we've tried our best to build more open spaces for our children," said Liu Bei, vice-principal of the school.

The education authority in Shenzhen, Guangdong province, on Monday released an opinion on improving physical education in schools.

Major breaks for physical activities at primary and middle schools in Shenzhen should not be shorter than 30 minutes every day, according to the opinion, which will take effect on Jan 1.

Students at primary and junior middle schools should have one physical education class each day while those in senior middle schools need to take three classes a week, it said.

Chengdu's education bureau also released a circular, emphasizing a reasonable study and rest schedule for students.

A primary school in Wuhan, Hubei province, carried out a plan to guide outdoor activities during the break between classes, stipulating that the time and space for activities should not be confined due to "safety problems".

Beijing No 161 High School has extended its breaks between classes from 10 minutes to 15 minutes.