Along with some 20 other Syrian children, 13-year-old Anas braves rain, mud and cold to attend class in a tent pitched along Lebanon's border with Syria, the home of a Syrian refugee family that serves as a classroom for four hours each day.

There are no benches and no blackboard. There are no textbooks and no notebooks. Just sheets of paper and some pencils and crayons that two young refugee women use to teach children like Anas how to read and write, count and draw, sing songs and recite poems.

But even Anas might be considered one of the luckier ones of Syria's long conflict, which reached its third anniversary Saturday. Nearly half of Syria's school-age children — 2.8 million and counting — cannot get an education because of the devastation and violence, UNICEF recently reported. The numbers might even be greater, a tragedy for a country where once nearly all school-age children completed primary school.

"They come every day, these sad parents, begging me to take their children to school," said Etaf Seif Abdel Samad, the principal of a public grade school in Beirut, where Syrian children learn with the Lebanese side by side.

She added: "They've lost everything in Syria and all they have in Lebanon is the interest in their children's future."

More than 2 million of those who should be in school remain in Syria, where classrooms have been bombed, used as shelters or turned into military barracks. Another 300,000 Syrian children don't attend school in Lebanon, along with some 93,000 in Jordan, 78,000 in Turkey, 26,000 in Iraq and 4,000 in Egypt, UNICEF officials in Geneva say.

Those numbers likely are higher, as UNICEF can't count the children whose parents didn't register with the United Nations refugee agency. Experts say that puts a whole generation of Syrians at risk of coming of age illiterate, lost to a war that has killed some 140,000 people already. UNICEF estimates more than 10,000 children have died in the violence.

The conflict has unleashed massive suffering across all segments of Syrian society, but the impact on children has been especially acute. Malnutrition and illness stunts their growth; a lack of schooling derails their education; and the bloody trauma of war sears deep psychological scars.

With no end to fighting in sight, Syrian refugees are increasingly desperate to have their children obtain the most basic education. They plead with principals to take them into Lebanon's overcrowded public schools, send them to makeshift classes in tents and offer them to mosques to study with sheiks.

At Anas' tent classroom, near Majdal Anjar, a border town in the east of Lebanon's Bekaa valley, children's drawings hung on the plastic walls and an out-of-season Christmas tree decoration dangled from the ceiling. Anas, the oldest of the children on a colorful carpet, wore a sweater and warm trousers, though he sat barefoot in the cold.

Anas was in fourth grade when his city of Homs in central Syria came under siege nearly three years ago. His school came under fire, his teachers fled, and so did his family. Neither he nor his five older siblings have been to school since.

"My school was beautiful. It had walls and desks and doors. I had many friends there," Anas said.

In the tent, there were toys and stuffed animals for younger children, as well as some children's English books. But informal teachers Hanadi and Dalal got the children's attention by telling them a fairy tale. Both women asked to be identified by their first names only for fear of harassment from authorities.

"It's not really a school, it's more of an entertainment," Hanadi said.

They teach children between 5 and 15. With the help of the international charity Save the Children, they try to offer children a taste of a life they would have lived had it not been interrupted by war.

"We are giving them the basics, letters and numbers," the 23-year-old Hanadi said. "We mostly try to bring some joy into their lives. They've seen too much bloodshed."

The lack of educational opportunities for Syrian children is the most pressing in tiny Lebanon, where the country's population has grown by two thirds over the past year alone because of the massive flow of refugees. More than a million Syrians have sought refuge in the neighboring nation of 4.2 million.

By the end of last year, school-age Syrian children in Lebanon — currently estimated at 400,000 — outnumbered their Lebanese peers by 100,000. Some 45,000 are now enrolled in Lebanon's public schools, UNICEF says, while another 32,000 attend two and a half hours of classes in the afternoon, mostly to catch up and improve their foreign languages skills to a point to be enrolled. Many struggle because subjects like math and science are taught in English and French in Lebanon instead of in Arabic.

The relief is palpable for those who find opportunities for their children. In principal Samad's public school of Wata el-Msaitbeh in Beirut, 36-year-old Syrian mother of three Naima Mohedeen brought her daughters to school, leaving her youngest girl at home because she's too young attend. Her family fled to Lebanon only four months ago and Mohedeen, who is illiterate, teared up when she kissed her girls and said goodbye at the school's entrance, adorned with a giant Lebanese red-and-white flag.

"I want them to learn everything so they have a future," Mohedeen said. "I want them to become somebody. Somebody smart."


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