"Where's your passport? Where's your visa? Move along, there, move along."
Clutching at the rusty wire fence, two teenagers glance nervously at each other as voices echo around them. One is confused by the clamour; the other looks close to tears.
They proceed warily through the airport checkpoint, until they arrive in the room that is to be their home. A low bed is crammed inches from a cracked sink. A dying plant sits on the windowsill, next to a Charles and Diana commemorative plate.
"There isn't a TV in the bedroom," says 14-year-old Olivia Young, horrified. "They don't have a stereo, or deodorant. It's so basic. Just nothing, really."
Then, prompted by the portable CD players they are carrying, she and her friend move into the next room and out into the leafy reality of their Buckinghamshire school.
Olivia, and her Year 10 classmates at St Bernard's RC comprehensive, are trying out Escape to Freedom, a new travelling exhibition which attempts to package the refugee experience into a 15-minute interactive lesson.
Pupils are given a set of earphones, which relay the stories of three asylum-seekers. While they listen, they move through a series of eight small rooms, which recreate the asylum- seeker's journey.
There is the border crossing, with wire fences, the back of a lorry, where pupils are crammed next to packing crates, and the tiny bedsit where refugees are housed as their asylum applications are processed.
The shock element is unrelenting. But this, according to Janet Oostuysen, education worker for the charity Global Link, which designed the exhibition, is the aim of the project.
"We keep our children safe in school," she said. "We don't take them to emotional places. But this is quite risky. We don't want to terrify them, but we do want to humanise the situation.
"Asylum is one of the important social issues of our day, so children need a critical awareness of it. They need to think beyond the headlines."
This is particularly key in the affluent suburbs of Buckinghamshire. Many pupils at St Bernard's have only encountered refugees as figures in newspaper stories or politicians' speeches.
"Being a refugee is kind of the same as being thrown out on the street, isn't it?" said Olivia Young, emerging from the exhibition. And, for 15-year-old Ryan Wescott, the novelty of deprivation is captivating.
Enthusiastically, he extemporises additional horrors: "They didn't even have a toilet. They might have to wee in the sink or something. But there are really people living like that."
Paul Cullen, St Bernard's citizenship co-ordinator, admits that few of his students have met refugees.
"Asylum is just a word that they understand vaguely," he said. "That's why they need something like this. They don't realise the conditions refugees are coming from."
However, Sam Piggott, 14, believes that the exhibition has given her a a new awareness. Wiping tears away, she said: "Some people are so obsessed with big houses and cars. But refugees can't even get a pair of shoes. I kept thinking, what if that was me? I wouldn't even last two seconds. It's just horrible."