What keeps your spirits up at school? Chances are it's not playground duty.
And it's definitely not the prospect of last lesson with Kayleigh and Year 9, although some teachers say it's the children who keep them cheerful and fulfilled. The most likely answer is your mates - what puts in the fun and takes out the stress of teaching is having friends at school.
One of the strange aspects of being a teacher is how little time you get to spend in the company of other adults. It happens in fleeting bursts - queuing for the coffee machine at break, in the toilets, or passing in the corridor. Yet many teachers have a much closer relationship with their colleagues than office workers who spend 40 hours a week sitting next to each other.
That's because there are some things only fellow teachers can understand.
After a particularly stressful lesson you need to talk to people who sympathise because they've been there - in the same room with the same class.
Ever tried asking your husband for new ideas to use in the literacy hour? Or taken your girlfriend to the pub to discuss a nightmare group of boys in your form? It doesn't work. When you talk to non-teachers about your day, their eyes glaze over. But your colleagues understand what you are going through.
Having mates on the staff isn't just about having an audience for moans and complaints. Friends can also help you relax and unwind; a joke in the staffroom can put you in a more positive frame of mind.
Within five minutes of arriving at Beauherne primary school in Canterbury, Kent, I've witnessed two teachers checking each other's hair for nits. Now that's what you call close. Andrea Raymen, 30, and Emma Shrimpton, 33, are getting married on the same day in August although, despite what the children might think, not to each other. "And I'm meeting Emma in America on her honeymoon," chimes in Fay Pilbeam, 24. Andrea and Claire Atkins, 32, travel to work together "so we only have 12 hours of the day away from each other". When they're not laughing, they're socialising. "Coming here has put the enjoyment back into teaching," says Andrea.
So, why are the Beauherne staff so happy and positive? Is it a quiet school with few problems, allowing plenty of time for the staff to cultivate friendships? Not quite. The school serves a deprived council estate and has only just emerged from five years in special measures. Andrea, Emma, Fay and Claire are four of the team who've helped put the school back on track.
As Andrea explains: "Because of special measures we all had to get to know each other very quickly."
None of the staff of eight has been in the school for more than two years, and in many ways the experience of turning the school around has bonded them; they've had three headteachers. "There is no one to blame for what's gone wrong in the past," says Emma, "and no one's being defensive." Andrea adds: "Everyone has to have a sense of humour, because if you took it seriously all the time you'd see too many problems. There are times when I've said I don't know where something is. And everyone else says, 'neither do I'. You have to laugh about things like that."
The women talk enthusiastically about the changes they have seen in the school, and their excitement is infectious. When Emma says: "People are keen to change and try out new ideas," the rest agree. "Instead of saying, 'we've always done it this way', it's, 'how should we do it this year?'"
says Andrea. "We had a big staff meeting one evening and changed almost everything about the school."
The staff at Beauherne work as a team, but these four are particularly close. "We started becoming a group when we came out of special measures and decided to have a girls' night out," says Andrea. But their relationships work on two levels. "Last year, I was Fay's NQT mentor and, despite being friends, we had to be professional. We needed to take each other seriously." Fay echoes this: "We have an informal relationship, but we know when it stops."
Professionally, all agree they have developed as teachers as a result of their friendship. "I've learned not to shout too much when controlling the class," says Fay. "Andrea and Emma have taught me how to be a lot calmer."
Andrea has become a lot more positive about teaching, and Emma observes that "you are a lot more relaxed in the classroom when you are happier at work". She also believes "it's good for the children to see healthy adult relationships when perhaps that's not always what they see at home".
With such enthusiasm and so much to talk about, it's probably good that the foursome have each other to bounce ideas off. "Otherwise," says Fay, "I think all our partners would have left us by now."
Joanna Williams was an English teacher at Herne Bay high school, Kent, where staffroom friendships kept her going after she moved south with a young baby. She is now a home tutor and writer