A cave's interior has been carved into cube-shaped rooms. Improvised lighting, barely strong enough to illuminate the cavern, shows children sitting, legs crossed, on the bare floor.
They are calling out boisterously, raising their hands eagerly, clamoring to answer questions.
These are some of the students in Syria who, because of civil war, have deserted their schools and taken classes literally underground.
An amateur video, posted by a local activist on YouTube, gives a glimpse of one of these cave schools, which is reminiscent of the stone schoolhouse from "The Flintstones."
Behind the citizen reporter, Abu Diyaa, is a group of first- through fourth-graders who greet him graciously with a round of applause.
"Why here?" Abu Diyaa asks a male instructor.
"We want to keep educating our children," says the teacher, who does not give his name. "But in the city, there is always this imminent danger that the regime choppers or planes will bomb us or drop the TNT barrels."
The school is in Kansafra, in a picturesque region known for its flowing green fields and its groves of olives, cherries and grapes. But none of that is visible from the classroom, which has no windows.
The children's previous school, in the nearby town of Jabal Zawiya, was deserted. Abu Diyaa's video shows a gaping hole in that school's ceiling, the battle scars of what he says was shelling by regime fighter planes.
Jabal Zawiya has been a target of indiscriminate bombing, according to Amnesty International. Most of its residents have fled.
"We are teaching whoever is left behind," says the cave school instructor.
While the cave's stone walls and its remote location offer protection, he says, it is still dangerous for the children to go to and from school. He groans about the lack of supplies, the small blackboard and the dim lighting.
Students behind him hold flashlights to help brighten the room.
"There is suffering, but, thank God, we are moving on," he says.
The teacher calls on a student seated on the floor to stand up and talk to Abu Diyaa on camera. Abu Diyaa asks the student what he would like to tell the government of President Bashar al-Assad.
"We want them to leave us alone," the boy says. "Enough killing and destruction. We've had it. We can't get close to our schools."
The Syrian government confirmed last month that more than 2,000 of the country's 22,000 schools have been damaged or destroyed. Through state media reports, it has justified its military operations on schools by saying that rebels have used them as bomb-making factories and weapon caches.
Because of restrictions on journalists by the Syrian government -- as well as life-threatening dangers involved with reporting from inside the country -- CNN cannot confirm the government reports or the authenticity of events depicted in social media.
Despite the turmoil around them, children in Syria still want to learn, said Pauline Rose, director of an annual education report published by UNESCO. The most recent report focused on education in regions beset with violence.
"Even in these conflict-ridden countries, there is a real desire for education. ... The children want to be able to learn," Rose said. "Those who were in school really had a desire to learn, and schooling gave them a sense of feeling normal."
Rose said aid organizations should boost education in their programs.
"Only 2% of humanitarian aid is spent on education," she said in a disappointed tone.
According to the UNESCO report, an estimated 2 million children around the world were killed in armed conflict during the decade leading up to 2008. Classrooms, children and teachers are often targeted for strategic reasons.
"All too often, armed groups see the destruction of schools and the targeting of schoolchildren and teachers as a legitimate military strategy," it said. "The problem is not just that schools -- and schoolchildren -- are getting caught in the crossfire, but that the very places that should provide a safe haven for learning are viewed as prime targets."
At the deserted school in Jabal Zawiya, Abu Diyaa's video reveals rows of empty desks. The hallway is empty, with the exception of concrete rubble where he says the shelling took place.