Mariam refers to her simply as "The Woman". It was The Woman who abused her for years, beating her and telling her that she was good for nothing. It was The Woman who kept her home from school, forcing her to cook and clean. And it was as The Woman lay unconscious on the floor, blood seeping from her head, that Mariam and her brother knew they would have to leave the country.
In that same moment, 14-year-old Mariam also resolved to go to university, to make a success of herself and to come back one day and prove to The Woman that she could amount to something after all.
Notoriously, children who are placed in foster care in Britain are unlikely to make it to university. Just 7 per cent of looked-after teenagers go on to higher education, compared with 40 per cent of their peers. The inability of teachers, social workers and carers to shift this statistic upwards has been the source of much governmental hand-wringing for decades.
There is, however, a notable exception to this rule of underachievement. In certain boroughs, the proportion of looked-after children going on to university is steadily rising. What these boroughs have in common is a large number of children who arrive in the country as unaccompanied refugees and are subsequently placed in care.
Mariam lost both her parents when she was a baby. The family was leaving war-torn Sierra Leone for neighbouring Guinea when her father was killed and her mother lost in the heaving mass of bodies. Mariam and her older brother were left in the care of a family friend.
"His wife was a really horrible woman," Mariam says. "She made us do all the housework. We were only allowed to go to school once in a while, basically to get people off our case. We didn't have time to do homework or nothing."
One day, The Woman began beating Mariam with unusual intensity. Mariam's brother stepped between them and pushed her away. She fell to the floor, hitting the back of her head, and was subsequently hospitalised.
"My brother said, 'We have to leave,'" says Mariam now. "'When The Woman gets better, things will be worse than they used to be. So we have to leave.'"
A teacher at school had previously offered to help them. Mariam and her brother took him up on his offer. He could help them leave the country, he said. "We would just go, disappear forever. We were happy to do that. I had this hope in my heart that we were going somewhere where life would be a bit better."
British children in care haemorrhage from the education system at 16, often ending up unemployed or in prison. But "better" for children such as Mariam inevitably means better-educated, with a university degree.
"Young people can be very resilient," says Sonia Jackson, professor of social studies and education at the University of London's Institute of Education. "Some of them say to me, 'I've seen so much, I've just got to make something of myself.'
"We can get hung up on qualifications. But education is good in itself. It helps people to make plans, not just to be knocked about by what happens to them. They're better-equipped to think about their situation and how they could improve it."
Medhi left Afghanistan before he turned 13. His father and older brother had fallen foul of the Taliban and the whole family was under threat. "They're looking at your family tree," Medhi says. "They want to destroy the whole tree, so a root doesn't come up again."
His mother sold everything she could to raise the necessary money to send Medhi away. He was told that he was going only to a neighbouring country - Pakistan or Iran - and that she and his younger brothers would join him shortly afterwards.
He was in the back of a lorry for two months. "We travelled at night, in the dark," he says. "You can't count the days because you're in the darkness. You're sealed in the back of a lorry. It confuses you, so you really don't know where you're going. We could have been in the mountains, in the forest, in the desert."
Eventually, Medhi had had enough of the darkness. He was cold and - with only survival rations - hungry. Surely, he reasoned, they had left Afghanistan by now. And so, when the lorry stopped, he jumped out and ran away. He headed for a nearby town, where he was directed to the police station: "I was messy and dirty and didn't speak the language. People recognise what you're up to immediately."
At the police station, a Farsi-speaking interpreter informed him that he was in England. "I remember in geography lessons we'd talked about America and England," he says. "They were big, big countries. I knew the names, but I didn't know where they were in the world."
He was placed with a small foster family in Tamworth, a town near Birmingham. "It's the worst, worst thing you ever feel, starting at a British school," he says. "My parents trained me to look after the animals - the goats and the sheep. But if you're not educated properly, you feel like you're blind. Learning things, going to university, helps you to communicate with people even better."
Never give up
Mariam speaks with similar sentiment. Her teacher in Guinea arranged for an agent to take them to Britain. Because he feared for his own safety, however, the entire operation was conducted on trust and suppressed information. She and her brother had no idea where they were being taken, even once the plane had landed and they emerged at Heathrow Airport. "I just knew this was a different language," she says. "It wasn't French, because I spoke French."
She now knows that the agent took her to south London. He stopped, pointed at a building and told the teenagers to go in there and ask for help. Then he drove away. It was December; it was cold. There was nothing for it but to follow his advice.
Despite their lack of English, the siblings were enrolled in a British school. "Going to school was horrible, actually," Mariam says. "They just put me in Year 10 and said I had to do GCSEs. And I thought, I don't even speak the language."
She would sit in the classroom, listening to her teacher speak and understanding nothing. "Whatever he's saying, I don't get it. I remember days when I just cried, when I didn't want to go to school at all. But that's the reason I came here - to have a nice life. I couldn't give up, so I kept on going and going. You don't give up because otherwise your life is going to be as horrible as it used to be."
But motivation does not spring purely from desperation. Other, more conventional factors also come into play. "Often, families will send the child who they think has the most chance of succeeding," says Margaret Aylott, head of Dormers Wells High School in west London, which takes in a large number of refugee pupils. "They'll choose the one or two, from maybe eight children, who will make the most of that opportunity. So there's already self-selection."
And, says Professor Sonia Jackson, family background can be significant in other ways, too. Foster parents in Britain tend to have very low levels of education. This has changed little since the 1970s. "They don't think of university for looked-after children," she says, "because they wouldn't think of it for their own children."
She has conducted detailed interviews with asylum-seeker children, as well as the broader looked-after population. She found that fewer than 25 per cent of the British-born children had fathers who had been to university, compared with 44 per cent of their refugee counterparts. By the time most refugees leave for Britain, they are in their mid-teens: old enough to have internalised their parents' ambitions. For them, university is simply part of the educational idiom.
"My idea about education was always 'I will go to college, I will go to university'," says Laila. "It was always part of the plan. My parents went to university and I would go to university."
Laila was 15 when she and her older sister left their home in Guinea. Her father had been part of the opposition movement; the government had responded by imprisoning her parents and setting the family home on fire.
A family friend came to pick the two girls up from school. She told them their lives, too, were at risk. "Usually the government takes everybody, the whole family," Laila says, "just to scare people more. So the best thing is to move away." The friend engaged an agent to take Laila and her sister to Britain.
'I can do this'
In Croydon, having sought asylum, the sisters were placed in a local school. "Oh, my goodness, it was so hard," says Laila. "I was not speaking English at all. I used to come back every day, crying. People were bullying me. Every day I was coming back saying, 'I don't want to go to school.'"
"Starting school in England, you're like a blind person," agrees Medhi. He had attended school in Afghanistan for two years - between the ages of 10 and 12 - but he says that the work they covered in that time would have been completed in two weeks at a British school. "There were no books. Nothing. You're basically going there to waste some time."
When he began Year 8 in Tamworth, he could read a little Farsi - his native language - purely because his parents had forced him to learn at home. "You start school and you can't talk, you can't read, you can't learn," he says. "You think you will never fit in, never learn to speak the language.
"But when you start putting in the effort, watching TV, playing a bit of football - that's when you realise you can speak to people. You think, 'I can do this.'"
Teachers play a vital role here: they remind refugee pupils that lack of language is not the same as lack of academic ability. "If we find that they're very able in maths, we'll put them in the top-set maths group and put a one-to-one maths teacher next to them to support them," says head Margaret Aylott. "If they're good at geography, we can timetable them so that they double up on two sets of Year 10 geography. It makes a difference."
Unlike conventional looked-after children, asylum-seeker pupils are often concentrated in particular areas. This means that schools such as Dormers Wells can focus on meeting their needs. "These youngsters don't achieve naturally," says Jane Featherstone. "You have kiddies with post-traumatic stress disorder. They've seen things no child should see. It's very much for the school to be proactive. It's about a supportive pair of hands - being a corporate parent."
Featherstone is deputy head of Gloucester Academy, which admitted 12 unaccompanied asylum-seeker pupils last year. "If they've got a home language or another language - say Arabic, if they're Muslim - we try to enter them for that GCSE," she says. "That way, they get as many results as possible." And the school will hold children back for a year if it improves their chances of good GCSE grades. "It's much better to accommodate them and meet their needs. Then they have a real chance of a good education. They just need qualifications, don't they?"
But, Aylott adds, refugee pupils can feel entirely lost in a British classroom. Some will not have used a computer before. Others may not even have seen a clock before: their understanding of time is limited to sunrise and sunset. Many will have no concept of subjects such as history.
"It's about understanding that they may have a low level of language, but they can have high cognitive skills," she says. Dormers Wells has a multicultural staff, so it is rare for Aylott not to be able to find someone for new pupils to communicate with. And the school offers breakfast and homework clubs, complete with internet use, so that pupils need not be disadvantaged by what is or is not on offer at home. "You can't make everyone equal," she says. "But you can provide opportunities so that they will thrive."
While Laila's school did not have large numbers of asylum-seeker pupils, she attended weekly sessions run by the Refugee Council, at which she was able to meet teenagers in the same position as her. And more significantly, she could meet other girls from Guinea, with whom she could speak French.
"I did a lot of thinking about back home," she says. "Thinking about my parents and stuff. But at least I had friends in the same situation. You form a family. You do things together.
"I didn't have English friends, because everyone was bullying me at school. But at least I had other friends. Even though my heart was bitter, at least I had people behind me."
Like Laila, Mariam was placed in a school with few immigrant children - unaccompanied or otherwise - and struggled to make friends. "They take your accent and just make a joke of it," she says. "They'd just repeat whatever I was saying. Even if people aren't talking about you, you think they are. It makes you feel really dumb, like you don't know anything. But I thought that, if I let them get to me, then I wouldn't be able to move on at all.
"Where I come from, education isn't that important, especially if you're a woman. As soon as you're 14 you have to be married, you have to have kids, stay at home. Education isn't for you. So I want to be an example. I want to help women in my country to flourish.
"I just woke up one morning and I thought, 'If I keep feeling this misery, feeling sorry for myself, I'll be like this all my life. Is that what I want? No. Just get out and do things. Don't be afraid to fail. Just keep going and keep going.'" She pauses. "In the end, I got better grades than those people who bullied me. Their GCSEs weren't that good."
Mariam achieved five C grades at GCSE and one E. She went on to take a business studies BTEC. Medhi sat eight GCSEs, scoring grade C or above in all of them, including A grades in maths and Farsi. He is now studying towards a BTEC in aerospace engineering.
"If anything, you feel sometimes they're doing too much," says Aylott. "Sometimes they're so keen to catch up with their work that we have to ensure they're not overdoing it. They might stay up, burning the midnight oil. Or as soon as they hand in an essay, they're asking if there's anything more they can do. Most of the time it's no bad thing: they really want to get it right. But you just have to make sure they don't push themselves too much. Keep a close, close eye on them."
After being in Britain for only a year and two months, Laila sat eight GCSEs. Her grades include an A* in French, an A in maths and Bs in double science. She went on to take A levels in maths, French, business and accounting. Now 21, she is in her third year of a finance degree at Kingston University.
"Some people, they're just not ambitious," she says. "We're ambitious because we think that this isn't our country. To be somebody in the future, you need to study. You need to work hard. Without any education, any degree, it will be really hard for us to survive in this society."
Now, after six years in Britain, she still has no information about her parents. "You never forget about them," she says. "But as the years go by, it gets less bitter.
"If you don't have family, you know you won't have any dad or mum behind you. You can't have your parents as backup. Your only backup is your own self. You have to do it yourself and nobody will come and do it in your place."
But higher education does not come easily - or cheaply - with no parental support. Medhi, now an 18-year-old with a strong Midlands accent, has twice tried to locate his family through the Red Cross, with no success. He has now received an offer to study aerospace engineering at the University of the West of England. But, without official refugee status, he is considered an international student, with debilitating fees to match.
"But I've worked so hard," he says. "I've been treated the same as everyone else and suddenly I'm different. People here take things for granted. I went to school and college with my friends and now they can go to university and I can't. What's the point of so many years and so much effort?"
Nineteen-year-old Mariam, meanwhile, is in her first year studying politics and international relations at Royal Holloway, University of London. She has worked part-time since she was 16 and manages her money with consistent parsimony. "First of all, you have to know what you want," she says. "Then plan what you have to do to get what you want. Sometimes, what you choose is not the best way. But failure is part of life."
Her ultimate ambition is to work for the African Union. "I always had this big dream, to be someone successful. To be a massive voice in the world. I just have to have the will to do it - the motivation inside of me.
"Definitely, one day I will go back to Guinea and I will find The Woman. In 20 years, I will go back and I will say, 'My life wasn't a waste at all. I didn't need you.' But I know that seeing her will be very emotional. I don't need that now. Now, I need to think about studying."
65,520 The number of looked-after children in England.
56% are male.
9% Increase in the number of looked-after children since 2007.
27,310 children went into care in the year ending March 2011.
26,830 children left care in the same year.
2,680 The number of unaccompanied asylum-seeker children in 2011.