By Enjoli Francis, David Muir and Christine Romo
At 6 a.m., just three short miles from the Syrian border, Hadija, 10, is awakened.
She gets dressed and within minutes, she walks hand in hand with her friend. No school bus is waiting though. There is instead a truck, with children spilling over. They are not going to school either today -- they are headed to the fields.
An urgent crisis is taking place halfway around the world, according to UNICEF and Beyond Association, a local organization that works with UNICEF to get refugee children access to schools.
According to UNICEF, there are nearly 600,000 Syrian refugee children in Lebanon and at least 300,000 of those children do not attend school.
The children of onetime teachers, government workers and engineers in Syria are now forced to work. Their families have run from the Islamic militant army of ISIS and other terror. The children – possibly as many as 300,000 of them -- work because the fields can pay much less than what they'd have to pay an adult.
It is the new normal for the children here, just over the border from Syria in Lebanon.
The children ride 20 minutes on the truck. Farmers, with idle tractors, await them. The boys make more money than the girls because the farmers say they are stronger.
Rather than attend school, many of them work in the fields, filling sacks with potatoes. For many, they are the sole breadwinners for their families.
They spend seven hours a day filling the bags. And it's not just the fields. Children work in factories, even auto repair shops.
Rami left his sixth-grade class in Syria, where his mother was a teacher. Now he works behind a desk in the back of a garage, fixing tires.
He tells ABC News that he misses "everything."
Even at night, the children work. Mohammed, 8, sells flowers on the side of a busy street. His sister stands across the way selling as well.
Nour, a Syrian refugee selling tissues to passers-by, says her mother died in Syria.
Many of the children, without parents and paperwork, get picked up by the police. Some of them are then brought to Home of Hope, a shelter for abandoned street children in Beirut and the only one of its kind in the entire country. Home of Hope's Sahar Tabaroni said she had 71 children, with some as young as 2.5 years old and some without parents.
Many of them crossed the Syrian border with their parents but were then separated from them.
"We don't even know who some of these children are," Tabaroni said. "We just go by the name they tell us. ... Some of them think they know a phone number and then can and call. And there's no answer. And that's the most devastating thing for a child."
Brother and sister Ahmed and Houda say they remember their parents as well as their home. Back then, they were allowed to play outside twice a week. The neighbors complained about the noise.
After seven hours of hard labor, though, some of the children leave the fields for a school run by UNICEF and Beyond Association.
"They come running here," said UNICEF's Sarah Shouman. "They'll be so exhausted. They're so excited. So you're trying to save at least part of their childhood."
When school ends, they return to the tents where they began their day.