Aid agencies estimate that there are at least 100,000 children trapped in opposition-held areas of eastern Aleppo in Syria.
The new academic year started last week, but as Syrian government and Russian air strikes rain down on Syria's second largest city, children are unable to go to school.
Some students, such as 13-year-old Nidal al-Aboud, are taking classes underground.
Nidal's school has been destroyed like thousands across Syria since the war began five and a half years ago.
Now his classes are held in a poorly lit and cramped cellar. The students do not go outside to play at break time as air strikes are more frequent now since the government's recent offensive began.
"I am scared because of the warplanes targeting us by air strikes. My friend was killed in my neighbourhood, we used to play together. A helicopter threw a barrel bomb on his house and he died," said Nidal.
His father worries he may one day not return home.
"As a father I'm happy when I see children going to school but because of the bombing I often feel that I'm sending my child to his death bed," says Abdulkareem Aboud, Nidal's father.
