Teachers who think that the only way to stay sane is to keep home and school strictly separate might gasp at the prospect of husband and wife teaching on the same staff. Yet couples who do teach together are surprisingly positive about it.

“It’s a real bonus,” says Pat Findlay. “We find it so helpful to be able to talk through the issues - kids, teachers or whatever - on a personal level with someone who understands the situation and its pressures.” Pat and her husband David Findlay teach at Ravens Wood School, a boys’ comprehensive in Bromley, where he is head of history and she teaches geography. They met at the school and married four years ago.

At the end of the day, the Findlays take a little longer to snap out of school mode than teachers who work separately, or who go home to a non-teaching partner. “For some, the first Friday gin and tonic marks the mental end of the school week. We probably talk school business for most of the evening,” admits Pat, “but it’s all gone by Saturday morning and we’re comfortably into private time.”

What happens about confidentiality? People who don’t have to juggle the spouse-as-colleague relationship often use an impartial husband or wife as a sounding-board when tricky issues come up. “It doesn’t arise with us,” Pat says. “We’re seen very much as a couple. We’re usually together at breaks, for instance. I think there’s an understanding that anything said to either of us is meant for us both.”

It is otherwise for Carl and Vicky Sharrat. They regard their respective jobs as head of art and science teacher at Thomas Telford School, a City Technology College in Shropshire, as discrete strands in their lives. “We actually see very little of each other during the day,” Carl explains, “because meal breaks are staggered and we have no staffroom.”

Apart from a bit of friendly ribbing by colleagues - Carl is considerably older than Vicky - at the time of their marriage last October, staff and pupils happily accept the Sharrats’ situation. “I think the students actually like us being married,” Vicky says. She and Carl don’t quite see themselves as two halves of one individual as the Findlays do, though. “I would always try to respect a confidence if it had been entrusted to me personally,” she explains.

Outside the school they avoid insularity by consciously anchoring their social life in friends who aren’t teachers. “It’s the only way to get any time out of school if you are married to a colleague,” Carl argues. “It forces us to switch school off.”

Several of the couples I spoke to argued that marriage actually works better if each partner fully comprehends the responsibilities and stresses of the other. A man or woman cannot feel excluded because of the demands of hisher spouse’s work if they teach in the same school. Nowhere is this truer than in boarding schools where term-time commitment is, effectively, 24 hours per day and seven days per week, even for non-resident staff. That is probably why the teaching couple phenomenon is more common in boarding schools.

Peter Lewis is head of science at Benenden, an independent girls’ boarding school in Kent. He and his wife Vivienne, who teaches music, are one of several married couples on the staff. Like the Findlays and the Sharrats the Lewises - they married in 1993 - met at school. Weekend and evening music keeps Vivienne at school for many hours. So do her twice-weekly duty evenings as assistant house mistress in a sixth-form boarding house. Peter manages a department of nine staff and three technicians and has many whole-school management responsibilities, including timetabling. Their hours rarely coincide and - unlike the Sharrats and the Findlays who talk of the practical advantages of sharing transport - the Lewises travel separately.

On the one hand they present themselves as separate people who work in different areas of a large campus. They deliberately avoid searching each other out at work or sitting together much in the staff common room. As Peter explains: “We get on with our jobs and we don’t bring our marriage to work. ” Vivienne even doubts that some of the younger girls realise that they’re married.

On the other hand their shared vision, common purpose and serious sense of commitment is remarkable. “The school is our life,” Peter says soberly. “We are both committed to boarding education and we love our jobs. It can cause enormous friction in a marriage when one partner has the total dedication you need to teach in a school like this and the other is elsewhere. Our personal staff meeting goes on for 24 hours a day but we’re very happy with that. ”

It seems that you simply accept the lack of time together in term time if you both teach in a boarding school, although the Lewises say they’re “pretty good at switching off” in the holidays and enjoy plenty of private time then. And at least if you teach in the same institution your holiday dates match exactly.

One partner being much more senior than the other can do strange things to lines of communication. If Vivienne hears colleagues whingeing about the timetable - a perennial staffroom gripe in most schools - she admits she feels awkward. “I try not to get too defensive but can’t usually resist pointing out mildly that although it may not be much good he was up until 3am doing his best - and I was there, too, helping him to check it!” If you’re married to the head it’s even trickier, as Jenny Haden finds. She is a part-time science teacher at Wymondham College, Norfolk, one of the few state boarding schools in Britain. “Occasionally I have to slip away if I think my presence is making someone feel uncomfortable,” she says, “but generally people are very friendly, and there isn’t a problem. People sometimes tell me things which they hope I’ll repeat to John - so it can work both ways.”

John Haden speaks warmly of the value of the extra support of having a spouse who is also a colleague. “We talk about and share things. Sometimes Jenny can tell me privately if I’ve really made a mess of something.” John and Jenny Haden have had plenty of practice at making their partnership work on all levels, having met at university in the Sixties and taught together in several schools before Wymondham. “It’s vital to take time off and get right away, ” says John from long experience. “We try to do it at least once a week by going out for a long walk, to the theatre or out to dinner with non-teaching friends on our day off. During leave weekends, half-terms and holidays we go to our house in Louth.”

Couples who teach together tend to enjoy it. Pat Findlay says: “We wouldn’t do it if we didn’t like it.”

Another key to success lies, apparently, in e-mail. Nearly all the wives and husbands I spoke to admitted to regular and secret marital communications. And messages such as “Can you let me have the Sainsbury’s list before you go to your meeting?” are quite commonplace.