At the unofficial schools run by Syrian activist group Kesh Malek in opposition-held districts of Aleppo, the children don't go outside to play during breaks in case a barrel bomb should drop from the sky.
With 110 teachers, most of them new to the profession, the organization runs seven schools serving around 3,000 children in the divided and war-ravaged city.
Syria's largest city before the civil war, Aleppo is the scene of heavy bombardment as the Syrian army, backed by Russian air strikes, tries to encircle it and wrest control of the rebel-held areas that are home to around 350,000 people.
Marcell Shehwaro, executive director of Kesh Malek, said the group's schools had closed for a holiday and had not re-opened due to the intensified bombardment in recent days. She said she did not know when they would re-open, but had not lost hope.
"When working on education you feel how important it is that there is another generation, and this generation needs to have a chance, the chance to have education," she told Reuters in an interview in London.
"We are thinking short-term. Let us deal with the situation as it is now. If Aleppo is besieged tomorrow, we are going to find a creative way to face that. It's all about resistance."
Kesh Malek has tried to locate its schools in basements surrounded by high buildings — that present clear targets — to provide some protection against aerial bombardments.
"Sometimes you feel ashamed of yourself, you are choosing places where others are going to be bombed and you are surrounded by protection, their houses are protection," said Shehwaro.
A former dentist who left the profession in 2010 to study political science, she later became an early participant in protests against President Bashar al-Assad that evolved into the civil war that has killed at least 250,000 people across Syria and driven 11 million from their homes. A Christian, Shehwaro serves Aleppo's Sunni Muslim community.
The name Kesh Malek means checkmate, or defeat of the king in chess, and refers to the group's ideal of creating a democratic republic in Syria rather than what it sees as Assad's dictatorship.
The group started setting up schools in Aleppo in 2011, at first using normal school premises, but that changed after a government bombardment in April 2014 on the Ein Jalout school in the city. Shehwaro said 23 children had died in that attack.
'THE NEXT VICTIMS'
"The worst case scenario is he (Assad) is going to target schools. Right now none of our schools have a yard. We don't have sports or this kind of activity," she said. "We replace that with drawing and puppet shows and indoor activities."
At first the schools were funded by the activists themselves and their local supporters, but over time foreign donors have offered support. Shehwaro cited Catholic aid groups Pax Christi and Development and Peace as major sources of funding.
Nevertheless, the flow of funds is irregular and sometimes teachers go without their salaries of about $115 a month.
Shehwaro said the group was political, but the children were not exposed to political slogans or campaigns.
"We don't want them to know about the revolution, but we want them to know they have rights," she said.
Gender is a major focus for Shehwaro, who describes herself as a feminist. Activities have included encouraging girls to formulate dreams for the future such as becoming a president or a carpenter, and one of the services on offer is home schooling for girls who married early.
Shehwaro said one of the difficulties was that 80 percent of the teachers were inexperienced, and most of them were women who had little access to relevant training as most programs available in Syria targeting women focused on areas like sewing or cooking.
"Let us break this view of Middle Eastern women … We should be enabling them in every sector they are trying to work in, not only what we assume is a sector they should work in."
Another problem is the psychological strain of war, which requires traumatized teachers to find creative ways to talk to children about themes such as death, hatred, and the future.
"The teachers themselves are burnt out, the students are burnt out," said Shehwaro.
"One of the teachers said to me, 'why are we teaching children who are going to die next week?' To me it's harsh, but it has its own logic. They look at the children and imagine that they are going to be the next victims."