HOMS, Syria, June 7 (Reuters) - In one district in the battered city of Homs, one school educates children while the other three shelter families who fled fighting in neighbouring areas more than a year ago.
Most of the 1,200 people camped out in the classrooms only expected to stay for a few days in the mistaken belief that the violence would soon end.
But as the weeks turned to months, a new order has taken hold - one where only the women can safely venture out, where the men live in fear of arrest, where a barter economy thrives and inventiveness has flourished.
"In a way, it's like a large prison," said a female resident of one of the schools, who, like many of the displaced people, declined to give her name for fear of reprisals. Most in the schools, which are in a government controlled area of Homs, are opposed to President Bashar al-Assad.
The Syrian Arab Red Crescent says up to four million people have been internally displaced within Syria by the rebellion against Assad, which broke out more than two years ago and shows no sign of abating.
With the humanitarian crisis worsening, the United Nations warned on Friday that half of all Syrians -- or more than 10 million people -- will need aid by the end of this year and called for $5 billion in emergency funds, which it said was the biggest such appeal ever made.
Homs, 140 km (90 miles) north of Damascus, is Syria's third largest city and an epicentre of the revolt, with fierce battles leaving 17 of its 21 neighbourhoods in rubble.
Shelling and gunfire continue in and around the city in restive areas. Further to the south, Assad's forces launched a successful counteroffensive to capture the town of Qusair this week, but whether they will push north to Homs or bypass it remains unclear.
Snipers, kidnappings and revenge killings make travel in most of Homs particularly perilous. Exactly who is behind such mayhem is hard to determine in the chaos of war, with pro-government residents blaming the rebels and vice versa.
Occasionally one of the men might sneak out of the school and try to cross the devastated city to see whether it is safe to return to their abandoned homes. It clearly isn't.
"We don't hear of them again. They disappear," said Fatma, a mother of four who used to live in the nearby suburb of Bayada.
The lurking danger leaves the school's unwilling residents stuck in limbo, surviving day-to-day as best they can.
Fresh food is hard to find, with young children starting to show the signs of vitamin deficiencies and mothers facing a dire shortage of baby milk, volunteer doctors say.
Disease poses a further threat.
Hepatitis A is on the rise as government-subsidised vaccines are no longer available, and an outbreak of Leishmania, a parasitic disease transferred through the bites of sand flies, needed some inventive thinking to bring under control.
To combat the illness, which can cause fever, breathing problems, ulcers and skin sores, a few residents, most of them unemployed engineers, managed to build an insecticide machine.
"Then we went to the municipality and begged for pesticide, and luckily they had some in stock. It was one month away from its expiry date," said one of the organisers.
Such resourcefulness is typical of school life. Recruiting carpenters and metalworkers from among the displaced men, they have built outhouses in the playground, and refurbished half-finished apartments to allow displaced families to squat there.
Since cash is hard to come by, workers get paid through a barter system. "You do my window frame. I'll do your door," explained one of the organisers.
Most of the men stick close to the school for fear of running into a government checkpoint, where they have to show their ID card. These documents clearly mark the origin of their holders, so men who come from restive areas known for harbouring armed rebels face immediate detention and questioning.
Death is perhaps one of the most complicated acts that can unfold at the school, as it creates "a nightmare of red tape and interrogations," said one of the residents.
"State security used to allow two family members to bury the body," said a young mother who recently lost a female relative, adding that the authorities were now suspicious of every death, probing for possible involvement in the rebel cause.
"They ask so many questions about how the death occurred, and they don't allow anyone to go with the body ... Inshallah they prayed over her when they buried her, but I don't know."
When families fleeing the nearby fighting started to arrive in previously affluent neighbourhoods, some locals realised it was for the long-term. One such resident, an art teacher named Ezza, decided not to give them any charity but instead tried to help them earn some money.
"Don't buy them fish, but show them how to fish," she said. "So I've been teaching some of the women how to do embroidery and art craft, and we've put together three exhibits so far, and sold their work."
Fatma, one of her best students, lives with her family and dozens of relatives. Asked how the men view her work, which brings in the only income, she laughed: "Sometimes my husband helps out by holding the ball of yarn as I knit."
Each classroom is shared by two families, with a makeshift wooden wall in the middle providing some semblance of privacy. A strict schedule dividing time and precious hot water among the resident families hangs at the bathroom entrance. Meals are eaten communally. Home life is a distant memory.
"We used to talk a lot about returning home. We don't any more. But the kids always have dreams," said Fatma.
"My daughter tells me: 'Mama, I saw myself walking down our street, and our home was still there.' And the other one says: 'Mama, I saw our home, but it was missing a wall.'" (Editing by Crispian Balmer and Giles Elgood)