Schools always welcome visits from former students. There's nothing nicer than mature 19 and 20-year-olds coming back to say hello, and tell you about progress in their lives.
But when ex-pupils go back to Whitefield School in north London, they are likely to get more than a handshake and a friendly chat. There's a strong chance they'll find themselves inside the staffroom being offered a job.
Because in the past few years, the school, a specialist sports college with sixth form buried in a monotone council estate in Cricklewood, has taken on four recent ex-students.
Their knowledge of school life, from the student's viewpoint, has proved an invaluable asset, and strengthened the bond between adults and pupils, in a school where once a "them and us" attitude marred relations.
About half of Whitefield's pupils are on the special needs register, with a similar proportion from homes where English is not the first language.
Despite this, exam results have risen sharply in recent years, and the school shines in all value-added measures. "Of course we have angry kids, and we have conflict," says Clive Baxter, deputy head, "but there's now no anti-school aggressiveness, and negative feelings are rarely directed at the staff." The former pupils on the payroll are key components in this improved relationship.
For Peter Blenkinsop, who's been at the school for 22 years, the last four as its head, the recruitment of ex-pupils is a natural extension of his policy of favouring internal promotions for all vacant posts. "Seeing former students come back as staff makes us all feel proud that our people have been successful," he says.
A striking example of that phenomenon is ICT teacher Jasmine Mohmoud, 23, (page left) now in her second year at the front of Whitefield's classrooms.
She speaks enthusiastically of the motivating effect it can have on pupils'
achievement when they learn of her background.
"They all say to me: 'Oh my God, Miss, you can't have come here and got a degree.' I tell them it's true, and say they can do it as well."
Darren Brain is the most recent staffroom arrival. The 18-year-old left last summer after taking A-levels. Now his main role is to organise the school council system.
He's already had an impact, by helping pupils launch their own Student Voice newsletter, soon to be sent out to every parent: a powerful symbol of the students' growing involvement with school life.
"Since Darren's been involved, the council is running much better, and we get more done," says Robert Stevens, one of the Year 8 representatives.
Nyangala Zolho, from Year 10, agrees: "He knows our points of view, and he knows how the teachers think too," she explains.
But Darren's role goes further. He assists Year 11 pupils with their coursework, helps with the daily management of the lunch queue, a potential flashpoint in any school, and takes his turn patrolling the corridors during lesson times. Here, particularly, he can use his inside knowledge.
"There's a place under the stairs by the MFL rooms, where I know kids can squeeze in and hide," he says. "I always look under there if I'm on patrol."
As I tour the school with the deputy head, another of Darren's strengths emerges. In a room for students withdrawn from lessons on behaviour grounds, Darren mentions one of the boys has just won a cross-country race, immediately creating the opportunity for positive conversation. "Darren epitomises just the sort of presence we need in school, to strengthen that link between staff and students," says Mr Baxter.
Daniel Hill, 19, is still friends with current sixth formers, but is already in his fourth term as a teaching assistant (TA). He left Whitefield after Year 11 to go to a local FE college, but stayed in touch. Last year, the school offered him a job. "I enjoyed my time at Whitefield and know the atmosphere, so where else better to start work than where you spent the best five years of your life?"
He spends most of his time in Year 7 and 8 lessons, giving one-to-one support to individual pupils, and, during breaks, keeps an eye out for friction around school. "Because of myage I know a lot more about what the kids are talking about, and I understand their street slang," he says.
The newest ex-student recruit to the staff room is Luke Baker, 23, who spent five years at Whitefield, leaving the school in 2000. He joined the staff as a TA earlier this term, and has found that his experience there as a teenager helps him in his job. "It's easier for me to connect with the kids because I understand what they are going through," he says.
It would be wrong to suggest that employing past pupils is responsible alone for Whitefield's improvement. That, says Mr Baxter, is down to many things happening dayily: all aimed at sustainable change creating a calmer atmosphere.
But he does admit to training his eyes discreetly on the current sixth form to try to identify who might be the next recruit
Facts and figures
Teaching staff: 83 full-time
Classroom support staff: 30
Support staff: 24
Percentage of five GCSEs A*-C in 2001: 21 per cent
Percentage of five GCSEs A*-C in 2006: 43 per cent
Target for five GCSEs in 2007: 50 per cent
Most recent value-added score for KS3 to KS4: 1009, KS2 to KS4: 1000.7
Number of permanent exclusions in past four years: 1
Not just a Whitefield
Debbie Burman has returned to teach at her old school just four years after leaving.
The former head girl at Stoke Damerel School in Plymouth says: "I'm doing my first year of teaching English at the school and I'm loving every minute.
"Some people might think it's strange having former teachers as work colleagues but it's been great. Now, instead of being the strange girl with pink hair that I was in the sixth form, I'm just another staff member."