More than five years of war, which began as a peaceful protest against President Bashar al-Assad and has since drawn in foreign military involvement and allowed for the growth of Islamic State, has displaced millions of Syrian children and limited their access to education.
With schools themselves at times attacked, teachers make do with the basics to provide education.
. Idlib, SYRIA. Reuters/Khalil Ashawi
Syrian student Ali Khaled Stouf has to walk down several steps into a hole in the ground to get inside his school - a cave.
There for four hours each morning, he studies subjects like Arabic, English, maths and religion, sitting on a rug with dozens of children in the underground space in Tramla, an opposition-held village in Syria's northwestern Idlib province.
. Idlib, SYRIA. Reuters/Khalil Ashawi
"I study in a cave. The conditions are not very good but the professor and his wife treat us very well," the 14-year-old, originally from neighbouring Hama province, said. "We sit on the ground and often we don't see clearly because it is dark."
. Idlib, SYRIA. Reuters/Khalil Ashawi
His teacher Mohamed and his wife, also from Hama, have opened up their underground home to teach some 100 children, whose families have been displaced by the Syrian conflict.
. Idlib, SYRIA. Reuters/Khalil Ashawi
Mohamed said the primitive, six-month-old school floods when it rains, forcing him to teach outside or in a tent, although he prefers the security underground. "We believe the cave is the safest place from shelling and air strikes and all the students are in one place," he said.
. Idlib, SYRIA. Reuters/Khalil Ashawi
Idlib province is a stronghold of insurgent groups including the al Qaeda-linked Nusra Front and has been regularly targeted in air strikes by the Syrian government, whose war effort has been boosted by the Russian air force.
At the Souriya al-Ammal (Syria the hope) school, in the town of Maarat al-Numan, corridors and classrooms are bullet-ridden and sometimes crumbling. In one less damaged area, walls have been repainted and the school now has some 250 pupils.
. Idlib, SYRIA. Reuters/Khalil Ashawi
"War has affected education massively; most schools, if not destroyed completely, are damaged," school supervisor Abdullatif al-Rahoum said, adding those who missed out on education are now playing catch up with younger students.
"The biggest challenges we face are the warplanes, which never leave the skies. This always worries students."
. Idlib, SYRIA. Reuters/Khalil Ashawi
In the nearby town of Saraqib, a mobile caravan serves as a classroom, run by a group aiming to reach children who have no access to schooling in the area.
. Idlib, SYRIA. Reuters/Khalil Ashawi
Lack of books is problematic. Teachers in Idlib said they relied on charities or used books printed in neighbouring Turkey by the opposition run Directorate of Education.
. Damascus, SYRIA. Reuters/Bassam Khabieh
In the rebel-held town of Douma, outside Damascus, Mounir Abdelaziz, a member of the opposition-run education body, said local schools were using old textbooks, but with changes.
. Damascus, SYRIA. Reuters/Bassam Khabieh
"We follow the same curriculum as the education ministry but with some modifications and articles related to the (Assad) regime deleted," he said.
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Slideshow
. Idlib, SYRIA. Reuters/Khalil Ashawi
A defaced picture of Syria's president Bashar al-Assad is pictured on a wall inside 'Syria, The Hope' school on the outskirts of the rebel-controlled area of Maaret al-Numan.
. Damascus, SYRIA. Reuters/Bassam Khabieh
Girls stand welcoming visitors with dates at the entrance of their school in the town of Douma.
. Damascus, SYRIA. Reuters/Bassam Khabieh
Girls sit inside an empty classroom during a celebration marking the end of the school year in the town of Douma.
. Damascus, SYRIA. Reuters/Bassam Khabieh
A girl wearing traditional men's clothing folds a cloth during a celebration marking the end of the school year in the town of Douma.
. Damascus, SYRIA. Reuters/Bassam Khabieh
Girls walk through a damaged corridor inside a school in the town of Douma.
. Damascus, SYRIA. Reuters/Bassam Khabieh
Girls wait in line during a celebration marking the end of the school year in the town of Douma.
. Damascus, SYRIA. Reuters/Bassam Khabieh
Girls wait on a staircase during a celebration marking the end of the school year in the town of Douma.
. Damascus, SYRIA. Reuters/Bassam Khabieh
Girls wearing traditional men's clothing serve coffee during a celebration marking the end of the school year in the town of Douma.
. Damascus, SYRIA. Reuters/Bassam Khabieh
Girls attend a class celebration for successfully completing the school year, in the rebel held besieged town of Douma.
. Damascus, SYRIA. Reuters/Bassam Khabieh
Girls sit next to a riddled wall in a school yard in the town of Douma.
. Idlib, SYRIA. Reuters/Khalil Ashawi
The group "Saraqib Youth Gathering" created a mobile learning caravan to reach children who have no access to schools on the outskirts of the Syrian rebel-held town of Saraqib.
. Idlib, SYRIA. Reuters/Khalil Ashawi
Children watch as a volunteer teacher takes part in a puppet show.
. Idlib, SYRIA. Reuters/Khalil Ashawi
A boy watches as volunteer teachers perform a puppet show.
. Idlib, SYRIA. Reuters/Khalil Ashawi
Internally displaced girl Yusra Ahmad, 13, attends a class inside a cave in the rebel-controlled village of Tramla.
. Idlib, SYRIA. Reuters/Khalil Ashawi
Internally displaced children attend a class inside a cave.
. Idlib, SYRIA. Reuters/Khalil Ashawi
Internally displaced girl Shahed Shahine, 13, attends a class inside a cave.