SABHA, Jordan » The parents were petrified the oldest of their seven children would be drafted into the Syrian army. For their teenage girl, they feared rape and kidnapping. And the next oldest, verging on adolescence, had begun rabble-rousing at school and in the street against the government.

So in September 2011, six months into the uprising against President Bashar Assad of Syria, the parents sent the three children — then 15, 13 and 11 — away from home in Hama province with about $425 and a tent sewed out of Chinese rice sacks. The children have lived on their own in Jordan ever since.

The eldest, now 17, picks vegetables for $8.50 a day when he can; the girl has learned to cook; the younger boy kicks a ball or plays cards. He has no actual cards, so he made his own, writing numbers on scraps of paper.

"I used to just be a child — now I’m the head of the house," said the 17-year-old, who spoke on the condition that he not be identified to protect his family in Syria. "I need a budget and to manage my money. I never thought of that before."

As the Syrian civil war rages into its third year, nearly one-third of the population of 22 million inside Syria needs humanitarian help, and 1.4 million have fled their homeland altogether. Of about 500,000 seeking shelter in Jordan, about 55 percent are younger than 18. Their troubles and challenges — years out of school, trauma from having witnessed the killing of relatives, sexual abuse — mirror those of their peers struggling to survive in tents and hideaways in Turkey, Iraq, Lebanon and Syria’s own shattered communities.

These children, the next lost generation, make up a particularly troubling category of collateral damage from Syria’s chaotic conflict, which has left 70,000 people dead.

There is Ahmad Ojan, 14, who wanted to be a teacher, but now spends his days peddling tea in Jordan’s sprawling Zaatari refugee camp. And there is Marwa Hutaba, 15, who still hopes to be a pharmacist, but is increasingly worried that she might be married off to a wealthy foreigner — like the 14-year-old who disappeared from school after "getting engaged one day and married the next."

"When you talk to them about the future," said Carolyn Miles, chief executive of Save the Children, "they can’t see beyond, frankly, the next day."

Children have been streaming across Syria’s borders for more than two years, thousands of them separated from their families. Even those accompanied by their parents arrive traumatized: A recent study by a Turkish university found that 3 out of 4 Syrian youngsters had lost a loved one in the fighting.

Before the war, more than 90 percent of Syrian children were enrolled in school; in Jordan about 1 in 3 of the refugees ages 6 to 14 attend class. The rest are left to learn the life of an exile, where guile and aggression matter more than books and tests. Where there is little to look forward to, only now.

In Zaatari, children dodge tear gas at near-daily demonstrations. They shake down water tankers to get their buckets filled first. They throw stones at aid workers. Gangs have formed, looting doors and windows from trailers and busting through fences.

"Nine-year-olds are coming to the swings armed: That’s a serious issue that we have to deal with every day," said Jane MacPhail, UNICEF’s coordinator for Jordan’s camps. "Your brain changes. Your ability to assess risk goes. What we have to do is reconnect these kids’ neuropathways to their emotional brain. Otherwise we’re going to lose this generation."

This small desert nation of 6 million opened its doors to the newcomers but was quickly overwhelmed as they gobbled up jobs, taxed scarce water resources and forced schools into double shifts.

About two-thirds of the refugees are squatting in Jordanian cities and villages, but the pathos and problems are most profound in Zaatari, where families live in row after mind-numbing row of tents or trailers, each day an endless cycle of finding food and water, clearing dust and debris, waiting in lines.

The camp opened last July and now sprawls across 5 square miles, costs $1 million a day to run and has a population of perhaps 120,000 — by far the region’s largest hub of refugees.

It is a vast jungle of humanity, and disorder. Electricity is pirated. Rations are brazenly bought and resold right outside distribution centers. Riots break out many mornings at three sites where the World Food Program hands out half a million pieces of pita, as boys scale barbed-wire fences to skirt the lines.

It is home, school, play — life — for these displaced children of Syria.

Ahmad Ojan, whose father died a decade ago, arrived with his mother and several siblings three months ago from Daraa. Each morning, just after 6, he heads to the bread line with a thermos of hot tea, which he sells for 15 cents a cup.

"Chai b’hayl," tea with cardamom, he calls in a slightly mournful wail. A few other boys pass with similar thermoses. An old man has one, too.

On a good day, Ahmad can make $8 to $10, refilling his thermos four times. After the bread line, he sells at the registration compound, trading tips about surviving in Zaatari for news from the front lines. Around sunset, he plies the endless, unregulated marketplace of corrugated tin stalls.

"It’s so easy, and I feel proud because I feel like I help my family," said Ahmad, who has been out of school for two years. Social workers in the camp encourage him to join activities, but "if I feel there’s potential to sell," he said, "I’ll make another flask of tea."

Ziad Hennawi, 15, lives in what passes for stability in Zaatari, having been among the first to arrive, with his parents and 10-year-old sister, on Aug. 23. With his mother earning $310 a month teaching at the UNICEF school, they have tried to make a home to mirror what they left behind.

There are two trailers set in an L, a kitchen, a toilet and a portable washing machine. There are coat hooks on the walls, a television, a fan and a private water tank.

But it is just a veneer of normalcy.

Each day, Ziad sets his cellphone alarm for 5 a.m. to get in line for bread. Later, he might put up tents ($5 each) or clean bathrooms ($12 a day), fetch the family’s water and drain its sewage.

Before leaving school in seventh grade, Ziad thought maybe he would be an accountant for his father, who owned two furniture showrooms in Homs. "Now the only future I’m thinking of is to rebuild my country," he said.

These are the life lessons for the children of Zaatari, where boys who have barely begun to shave learn to fend for their families — and girls learn how to avoid the advances of adult suitors.

Marwa Hutaba, the 15-year-old who wants to be a pharmacist, said she had become more religious since leaving Daraa, donning modest dress and carrying prayer beads. One day after school, a Saudi woman seeking a wife for her son pulled Marwa aside.

"I told her I’m young, I don’t want to marry off at this age," Marwa said. "I wish that I don’t grow older, because the older I grow, the more attractive I become to people."

But however circumscribed their lives, these children have more safety and stability than the siblings living in a rice-sack tent.

About an hour’s drive on back roads from the camp is the shantytown near Sabha where the teenagers from Hama have lived for five months. It is half a mile from the Syrian border: Army tanks are visible in the distance, bombers heard overhead. They have not been able to reach their parents by phone for two months.

The eldest said he got farm work about once every 10 days, and when he cannot buy food, relies on neighbors in the makeshift camp. In February, they registered with the United Nations refugee agency, and have since received a food coupon worth $48 and visits from the International Medical Corps.

But the agency does not plan to find foster care for the siblings, or move them into an apartment. "He’s proven he can keep the kids safe," said Mary Jo Baca, a mental health adviser from the group, said of the eldest. "He’s a survivor."

Their homemade tent is large. The tree branch holding up the center is adorned with circles of salmon-colored sequins brought from Syria. In the back, two plastic crates hold jars of olives, cheese, lentils; the girl pickles whatever vegetables her brother brings, so they last.

The girl wore a blue head scarf to match the sequins on her black abaya. Her eyes were also lined in blue. "I have my makeup from Syria," she said. "It makes me feel a little bit better to have makeup on."

The 13-year-old is bored and homesick. "I had a better life in Syria with my parents and my friends," he said. "I just want to go to school."

© 2013 The New York Times Company