CHONGQING - Cold rice. A few slices of dried beancurd. Tan Biyue takes the same lunch box to school every day.

The eight-year-old never complains, knowing it is the best her aging grandparents can prepare for her.

Her real agony comes from missing her parents.

Tan's mother, fed up with the tough life in the poor village in Southwest China's Chongqing municipality, walked out when Tan was still a baby.

Unable to support the family on the meager farming income, her father spends most of his time in the country's south, working as a migrant worker.

"I cannot remember what my mom looks like, but I'm sure she's sweet," said Tan, her eyes filled with tears.

Lonely childhood

Tan belongs to a lonely group that is known in China as left-behind children -- an estimated 58 million children who are cared for by a single parent, grandparents, and sometimes a distant relative or even a neighbor.

Their parents have migrated to cities in search of work.

Of all the 58 students at Tan's Caoping Primary School, 35 are left-behind children.

Across Chongqing, the number of left-behind children is estimated at 2.35 million.

"My parents came home to celebrate the Moon Festival two weeks ago," said Tan's classmate Huang Yinshen. "My friends were so jealous that they didn't talk to me for days."

China Youth and Children Research Center found in a survey that more than 57 percent of the rural left-behind children suffer psychological problems, including cowardice, self-contempt, belligerence and resentment for their parents.

Child psychologist Wei Zhizhong, however, believes the percentage could be even higher.

"Almost 80 percent of the left-behind children have problems getting along with other people," said Wei. "Some are autistic and lack basic communication skills, while others are defiant and hostile."

Last week, three girls, aged from 10 to 12, jumped off a two-story building in the Eastern Jiangxi province, fearing they might be punished at school for failing to finish their assignment.

All the girls survived with injuries,as tree branches broke their fall.

The girl who thought up the suicide plan, 11-year-old Huang Jing, is a left-behind child. Her parents work as migrants in Jiujiang's city center and are rarely home.

"We should take a lesson from this tragedy and care more for these left-behind children," said the school principal Zhou Liangqi.

The local education authority has also called on schools to provide counseling to these students.

Safety concern

Due to a lack of caring, left-behind children often become victims in accidents and natural disasters.

Earlier this month, two preschoolers died of suffocation after being left on a school bus for more than eight hours.

The girls were both left-behind children and had apparently fallen asleep when everyone else was getting off the bus.

Of the 12 people who were drowned after a ferry sank in central China's Hunan Province in early September, nine were left-behind children, including eight primary school students and a junior high who were taking the ferry home after school.

Left-behind children accounted for at least half of all the 20,000 minors killed in accidents across China in 2008, the most recent time that data are available, according to a report published by All-China Women's Federation.

It said 34 percent of the caregivers for rural left-behind children surveyed in 2008 said they cared about children's safety "only occasionally." Eight percent of them said they were always too busy even to think about the safety issue.

The report quoted police authorities as saying that left-behind children in the countryside were the second biggest target for child traffickers, next only to migrant children in cities.

Helping hand

Starting in 2003, Chinese central and local governments made new policies encouraging the society to take over parents' role in caring for the left-behind children.

Across China, more than 7,600 boarding school and 6,500 nursing homes have been set up for left-behind children.

In addition, at least 30,000 family education service providers have opened their arms to left-behind kids, with 3.15 million volunteers working as their "acting parents."

Wang Xiaolong, 12, attends a boarding school in Qijiang County in outer Chongqing and visits his grandparents on Fridays. He spends weekends and holidays at his village's nursing home, accompanied by his peers and volunteers.

"The food is much better: at home we only have potatoes; but here we have meat almost at every meal."

Starting in 2007, a government-financed "egg and milk project" was promoted in rural schools to improve nutrition for the children.

In Chongqing alone, the project has benefited 2.78 million students at more than 5,000 schools.

"I rarely had eggs or milk at home," said Chen Quan, 7, who stays with his grandmother most time of the year. "I can't ask too much. My grandmother is 65 and still toils in the field."

Though most rural families have a chicken coop, eggs are often saved for sale. Milk, on the other hand, is rarely considered a must on the breakfast table.

An industrial park under construction in the suburbs of Chongqing carries many children's hope of being reunited with their parents.

"Factories will move into the park and offer jobs to local peasants when it opens," said Wan Tingxiu, head of a nursing home in Qijiang County.