Tap 1, 2, 3, 5, 6, 7, 8. Tap 1, 2, 3, 4, 5, 6, 7, 8. In a Wiltshire school hall, 15 women and one man mambo back and forward, then rumba side to side. They giggle. They hoot. And when the teacher calls out, “Put a shimmy into it!” they shake their bottoms with abandon.

“If you’ve danced together, it does help your working relationship,” guffaws Barbara Booth, head of lower school at the Stonehenge school in Amesbury. “Anything is possible.”

Extra-curricular activity is big at Stonehenge (judo, go-carting and musicals for students - assisted by a New Opportunities Fund grant - football, aerobics, Spanish and relaxation for staff). So when Mrs Booth received a flyer about salsa and meringue classes, she pinned it to the noticeboard with a sign-up sheet. “It was something different,” she says.

Twenty people - teachers, teaching assistants, administration and secretarial staff, and teachers from feeder primary schools - have gathered to learn salsa dancing every Friday afternoon this term. They start half an hour after the final bell, fighting off the temptation to carry on working when the pupils have left.

“It’s a great wind-down,” says design and technology teacher Doug Grainger, the only man in the group. “For an hour it stops me thinking about school at all. I don’t work after that. I used to work and work and work all the time, but this gives me half an hour to get everything done, and if I don’t get it done in that half-hour, then I’m not doing it.”

Like many schools, Stonehenge has a long tradition of Friday night football. As the mostly female salsa dancers go through their moves with freelance teacher Melanie Keen, most of the blokes are in the local leisure centre. Class members shrug off the gender imbalance. But it causes confusion (and hilarity) when it’s time to partner up and one full-bosomed woman asks another: “Are you a boy or a girl?”

“They’re doing well,” says Melanie. “They’ve all kept up. No one’s dropped out thinking ‘Oh no, I can’t do this’. And I’ve noticed that, being teachers, they’re good at helping each other.”

She switches on the CD player, Enrique Iglesias croons “Escape”, and the dancing begins again. It’s only their seventh lesson, but most of the group are way past the stage of staring anxiously at their feet. They’re assured, sultry, hips swaying and hands gesturing flamboyantly as they step through a series of three-quarter turns. Those who aren’t smiling broadly are frowning in concentration - or pain.

“Cor, me arm’s aching,” complains one woman. It’s not just arms that ache. Salsa is a workout. “It’s a constant wiggle-wiggle-wiggle with your waist and hips and bottom,” says Ms Keen. “It really burns weight. And people don’t realise they’re exercising; they’ve got too much to think about learning new steps, and it’s fun.” The salsa class will feature prominently on the school’s application for a Healthy School Award.

Headteacher Andy Packer sees benefits beyond exercise: “It’s about communication, it’s about a sense of school community, but the single most important element is laughter, fun. If people invest their time in this, it means that later, when there may be a school issue to deal with, they have an emotional account with each other. That helps ensure the smooth running of the school.” Involvement of feeder primary schools (Amesbury junior and Christ the King junior) yields the same benefits: teachers who have played together have a better chance of problem-solving together.

Meanwhile, there’s serious toe-tapping going on around Wiltshire - the teachers are doing their homework. Kay Davies, Years 5 and 6 teacher at Amesbury junior school, says: “I don’t have net curtains, so people can see straight into my house. I don’t know what the neighbours think, because they can’t hear the music. They can only see me doing this (she sways her shoulders seductively) while I Hoover.”

Others keep it in school. “I’ve practised in the classroom when the kids aren’t watching me. They’ll be getting on with making stuff and I’ll be secretly tapping my feet,” confesses Doug.

The secret will soon be out. At the end of the lesson, Melanie announces that there will be a fundraising performance at the Salisbury Arts Centre next March, and suggests that the group take part. No one shakes their head, or shuffles nervously towards the door. They’re hooked.

Salsa clubs, classes, events and teachers are listed by region at http:www.salsajive.co.uk. Melanie Keen: keensalsa@aol.com. Details of the Healthy School Award: www.wiredforhealth.gov.uk