The house is filled with children, but has little of their laughter. These boys and girls have lost a big piece of their childhood to long hours and rough treatment working for fishermen.

A few bounce balls or play games on the porch. Others help with the laundry. But on a bright summer day, most are draped listlessly over the furniture, sleeping or staring into space, while the international aid group that freed them tries to trace the parents who sold them into virtual slavery.

Their future is uncertain, and the fight against child trafficking in West Africa is far from over. Only last July did Ghana's parliament pass a child trafficking law, and it still awaits the president's signature.

Among the children is 15-year-old Kwabena Mensah. He says his mother sold him as a fisherman's helper when he was 8, hoping it would be a short stint to pay his way through school. Instead he spent seven years doing a dangerous job 13 hours a day, earning little beyond regular beatings from the man he calls "my master."

"It burns me to know that I spent my life with my master, because whenever I walk with people my age and they're talking about school, I can't say much, because I spent the life I should have had in school with my master," Kwabena said.

Kwabena was among more than 100 children rescued earlier this year in Yeji, a fishing community on Lake Volta, 300 miles from Accra, the capital. The International Organization of Migration, an independent agency known as IOM, says it has reunited 537 children with their parents or other guardians since launching its Yeji Trafficked Children Project in December 2002.

Fishermen or go-betweens typically promise between $20 and $120 plus future wages for children as young as 4. The parents rarely see more than the initial fee, and the children are often beaten and poorly fed. Fishermen value them for their small hands, making them dive to disentangle nets. Some drown.

IOM workers say nearly all the children they have freed tell of beatings, irregular meals and harsh living conditions.

"These are coastal communities, and it's an age-old practice," said Cromwell Awadey, a Ghanaian research officer with International Needs Ghana. His independent group is working with the International Labor Organization and the International Program on the Elimination of Child Labor, both U.N. projects, to raise awareness in Ghana of child trafficking.

Project director Joseph Rispoli, an American, said nearly all the children have suffered malaria, amoebic diseases and psychological trauma. Apart from medical care, "most children need at least a couple of years of regular counseling in order to heal," Rispoli said.

His organization offers fishermen small loans and job training in exchange for freeing the children.

Gabriel Kudomor, a fisherman for 23 years, released 13 children in 2003 and set up a poultry farm with IOM assistance. He now helps the IOM by speaking out against child trafficking.

"Too many children were dying," he said.

Once the children are freed, IOM rescuers use information provided by the fishermen to find parents.

"We give them back to the people that sold them, because there aren't too many options," Rispoli said.

The task can be difficult. Empty-eyed Abena was sold a year ago and no longer remembers who her mother is. She is 5 years old and doesn't know her last name. Neither does the fisherman for whom she worked.

Rescued children spend two months at the house on the outskirts of Accra, where doctors, nurses, social workers and psychologists are on hand round-the-clock to rehabilitate them.

For Kwabena, it's heaven. "We play free, we eat free, and nobody beats us," he said softly with a slight smile. He is about to be released to the mother who sold him. His hands still shake.

IOM says it offers funds -- paying the returned children's school fees for two years -- and job training to parents to dissuade them from selling their children. Many of them see selling their children as the only way to get them an education. School fees in Ghana are about $5 a year, but books and mandatory uniforms can add $60, or about two months' earnings in a country where half the 21 million people get by on a dollar a day.

The International Labor Organization estimates that 1.3 million Ghanaians under age 18 work in cocoa fields, fishing, as domestic servants or in other jobs. The U.S. Labor Department says the most common forms of internal trafficking in Ghana involve boys from rural areas who fish in the Volta region.

While no official numbers are available on the scope of children trafficked onto the waters of Lake Volta, Emmanuel Agyapong, a Ghanaian with IOM, says the problem goes beyond Ghana.

"We realized that wherever there's fishing, fishermen use children," Agyapong said.

"When you go to the places of origin of these children, you can see there are schools without schoolchildren," he added.

Even if child trafficking is outlawed, it's unclear where Ghana will find the means to arrest and prosecute violators or cope with large numbers of freed children.

"There will be the burden of reintegration of victims in society. This will be a problem for the social welfare of the country," said Jack Dawson, a Ghanaian with IOM.

But the job needs to be done, he said. "They have talents buried in them. We need to free them so they can develop their talents."

Children rescued from their "masters" by nongovernmental organizations sit at a rehabilitation center in Accra, the capital of Ghana. Poor parents sell their children to fishermen as helpers.