Just imagine: it's your first day as head at your new secondary school and you're meeting your staff for the first time, keen to make an impression.
Some of the faces in the staffroom look familiar - older than you remember, but very familiar all the same. Then you realise it. The faces looking back at you are those of your former teachers.
Ending up back in your old school may sound like one of those anxiety-induced dreams you get before starting a new job. But this is reality for a small number of headteachers who have gone back to run their alma maters. Take Tony Billings, 44-year-old head of All Hallows Catholic High School in Macclesfield, Cheshire. He left after taking his A-levels in 1981, and returned to run the place last September. He was astonished to find that five of the original staff were still there. And fortunately they brought back fond memories. He recalls that one teacher, Marie Browning, carried on teaching him and his fellow pupils their A-level RE course at her home, as she was on leave from the classroom while adopting children.
Another, his former social studies teacher Bernard Price, who is due to retire at the end of this year, he still associates with lessons on sex education, Cider with Rosie and a video about sexually transmitted diseases.
So how did they react when young Billings walked in as their new headteacher? "One of the teachers is rumoured to have said: 'ooh - I hope I treated him well'," Tony laughs. "They were just really curious and asked me lots of questions about where I had gone. They wanted to know about me as a person. Sometimes in leadership you go in and it's the position they see, not the person. Being a former pupil allowed me to break through that much more quickly."
But why go back to run your old school? Tony says he loved the place and wanted to put something back. His own education had influenced him enormously in his decision to go into teaching.
"I had failed my 11-plus and gone to a secondary modern. When I came to All Hallows in my third year, a whole new world opened up to me educationally and socially. For that reason I'm very committed to all ability education and schools which have a good social mix. All Hallows was - and is - a very inclusive and caring school."
Jan Buckland, aged 48, returned to Kingsholm Primary School in Gloucester as head six years ago, after its retiring incumbent persuaded her to apply for the post. It was seeing the school again after 30 years that persuaded her. "I just saw huge potential," she says. "When I walked into the key stage 2 building, which was my old junior school, it had hardly changed in all those years. And I just had that feeling that I wanted to come back. I liked the feel of the school and thought I could bring something to it as head."
After taking up the post, did she find old memories flooding back? "Very much so - even as far as doing handstands against the wall. I remember needlework lessons. And I can vividly remember my first classroom and my first teacher."
That first classroom is still there, though now it's a playroom for early years. Standing in the doorway, Jan points out how it used to be: "That was the door into another classroom, the blackboard was there and the cloakroom was there. And I sat there, in the middle at the back."
She says the school hall has barely changed - some walls still have the original grey, one of the old school colours. "I think the time it really hit me that I had been a pupil here was at the end of my first year, at the Year 6 leavers' service. I just vividly remembered sitting on the corner of that stage with my cello playing a solo."
Today Kingsholm Primary has smart new buildings for key stage 1 alongside its 1960s ones, and there's a planned new children's centre in the offing.
Jan says her experience as a former pupil has proved to be an asset in terms of running the school. "It was quicker and easier to make relationships with parents having been a pupil here," she says. "And there's a huge mix of children - we have white English, EAL (English as an additional language) children, and gypsy and showman travellers. It's a healthy mix. Having been a pupil here, and having had traveller friends, I wanted to make sure their beliefs and cultures were celebrated."
Sue Lymn-Brewin, 48, returned to the idyllic village primary school of her childhood in 1999 as a deputy and was appointed head of Gotham Primary in Nottinghamshire 18 months later. She says her years there as a pupil in the 1960s were very happy, clouded only by the memory of the school's irksome outside loos. "One of my earliest memories was having to dart across the playground with the rain bouncing off your legs to get to the toilets," she says.
"The curriculum has changed beyond belief, though we are moving back towards the kind of curriculum I had in the 1960s, the topic-based curriculum."
The school is now in new accommodation just across the road from the original Victorian building where Sue went as a child, now disused and up for sale. Has being an ex-pupil affected her style of leadership? "I think I have a passion for the school and it's perhaps more intense because I have this personal contact with it."
She describes the village of Gotham as a static community. "When I came back I had children in my class whose parents I had been to school with, and I knew their grandparents because I used to go and play at these grandparents' houses."
But that wasn't the only thing familiar at Gotham Primary. Teacher Heather Palmer, who is now approaching retirement, was a newly qualified teacher when Sue was a pupil there, and taught her in Year 5.
"I remember when I got the job saying to her: 'You set me on this road',"
Sue says. "And so she's still here, and has worked alongside me as a colleague."
She also finds her background helps her to empathise with her pupils, particularly when talking about their own aspirations. "I say to them that from here you can be anything, and whatever tree you decide to climb, you can go right to the top. It's a powerful thing to be able to say to children: 'I know what it's like to be you'."