Widespread suspicions over Western morals in schools,
mean that girls in northern Nigeria rarely go to school
Nigeria holds the record as Africa's top energy producer and most populous nation, but it also holds less enviable records - like being one of the worse places in the world to be a schoolchild.
In the traffic-choked streets of the northern city of Kaduna, boys as young as 10 squat at bus-stops, crowding the dented buses that judder to a halt.
They jostle and shove around the doors, fighting for a few hours' work as a bus conductor.
One child is picked - the others melt back, to sit amongst the dirt, awaiting the next chance.
Thirteen-year-old Aminu Harona's eyes scan the road.
''I don't have any money, and my parents are poor, that's why I do this," he says.
''I just want to earn some money, to help my parents.''
Thirteen is old in this job, and Aminu works harder than he did three years ago.
The bus drivers tend to pick younger boys: They are considered less likely to pilfer money from fares, and are better at scrambling around the crammed vehicles.
''People do not value us. I just wish to go back to school, to learn what I can do in my future," says Aminu.'Carried away by love'
More than half of the 8.2m children out of school in Nigeria are in the north.
The streets teem with impoverished youngsters, sprinting amongst heavy traffic, selling water and food.
In spite of Nigeria's public commitment to universal free education, less than 50% of children in northern Nigeria attend primary school, and only one in three is female, according to the Campaign for Global Education.
Local traditions of early marriage, and widespread suspicions over Western morals in schools, mean that girls are extremely unlikely to go to school.
"I was carried away by love. I was eight and I left school, because I wanted to get married," exclaims Hauwal Tijjani, frowning.
Her parents followed the local traditions in the villages: She was married by the time she was 13.
But by 16 her baby had died, and her husband divorced her - a pattern familiar in the region.
Hauwal spoke to the BBC amid the hum of sewing machines at the Tattalli Free School, a charity in Kaduna's back streets.
More than 30 students at the school are teenagers who are now divorced.
"It is poverty," says Rukayyat Adamu, the school's organiser.
"In the villages, the parents can afford nothing," she says.
"There is no money for schooling.
"There is nothing to do but to just marry the girls out."
Hauwal now sees her adolescent marriage as a mistake, and struggles to support herself.
"I had done the greatest damage to myself anyone could do," she says, softly.
"I wasted my first years of opportunity, and I want to do important things with my life."'Conniving officials'
Nigeria's untapped youthful potential is dizzying.
Seventy-five million - more than half the entire population - are under 18 and experts say another 68 million will be born by 2050.
Currently, one-third of school graduates are unemployed and analysts warn the economy must dramatically expand to keep pace with the demand for jobs.
"It all begins with education," says a local teacher, Jibril Suleiman Zakirai, guiding us through Unguwar Shanu local market.
A lucrative trade in the illegal sale of educational materials is clearly apparent, which local teachers say is crippling their work.
"It makes my heart bleed," says Mr Zakirai, in disgust. "These books are supposed to be distributed freely to the pupils in the schools."
The brightly coloured grammar and other text books dotting the stalls are clearly marked ''Not for Sale'' and ''Property of the Government of Nigeria''.
Only those parents able to afford the price can buy them.
"It is disturbing, glaringly clear," says Mr Zakiary. "Somehow, officials are conniving with storekeepers, to sell these."
He snorts in anger as the bookseller asks whether we want to buy a bulk consignment of the books.
"What little the government is providing, is not even going in the right direction," he says in frustration.
"Nigeria's children are being robbed."