The 12-month prison sentence imposed on Paul Ellis sent shudders through staffrooms all over the country. Mr Ellis, a geography teacher at Fleetwood high school in Lancashire, was leading a school trip in the Lake District during which a 10-year-old boy drowned.

After the trial last year, the NASUWT, the second biggest teachers’ union, renewed its long-standing advice for teachers not to undertake such trips.

There were horrified comments in the press from people who were appalled that a man giving up his free time to take children on an educational outing could make a mistake and go to jail as a result.

But Paul Ellis was not made a scapegoat. He is not in prison because it was his name on a risk assessment form, or because he was the leader of the trip.

“It is most certainly not a case of ‘There but for the grace of God go I’,” says Ken Ogilvie at the Institute for Outdoor Learning. “He was prosecuted, he pleaded guilty, and he has been imprisoned for one reason, and one reason only: he acted with criminal recklessness.”

A few facts might underline this point. Mr Ellis had decided to go “pool jumping” in Glenridding Beck. You jump into a mountain pool from a vantage point, an exhilarating experience, but a safe one - as long as the conditions are suitable.

But conditions were not suitable: there had been torrential rain and 10-year-old Max Palmer, the youngest in the group, got into difficulties.

Max’s mother, on the trip as a classroom assistant, jumped to his help, only to be overcome by the conditions. She lost her grip on her son who was swept downstream to his death The mountain rescue team who arrived to recover Max’s body described the beck as “a raging torrent”. One member got into difficulty after he was swept off his feet by the force of the water.

An RAF team had visited the beck earlier in the day. They took the view that it was not even safe to attempt to try and cross. A party from Lancaster grammar school was next at the plunge pool that morning. Their leader immediately decided it was “manifestly unsafe”, and they were walking back down the mountain when they met the Fleetwood party. The Lancaster leader warned Mr Ellis about the dangers. But Mr Ellis replied, “It’s alright, we have safety equipment. We have a rope.” In fact, he had left the safety equipment behind.

After a previous tragedy, when two girls died on a school trip to Yorkshire, Marcus Bailie, chief inspector of the Adventurous Activities Licensing Authority, pointed out the importance of local knowledge. Yearly visits to a venue are not enough. “Conducting an activity once a year for seven years is not seven years’ of experience - it’s seven days,” he says.

And teachers should emulate professional instructors, who have a back-up plan - a plan B for every activity. “The hardest decision is when you have to say No,” says Brian Davies, head of the Kilvrough Outdoor Centre in south Wales. “Inexperienced people don’t have the confidence to turn back.”

The day’s events at Kilvrough are decided every morning at a meeting between the visiting group’s teachers and the centre staff. But the weather can still disrupt plans. “If we are out on the cliffs and the wind builds up we withdraw and go somewhere else,” says Mr Davies.

At the Arthog Outdoor Education Centre near Barmouth, Andy Hall, the head of centre, has a similar routine. “If we’d planned gorge walking and the weather closed in, we might look at a smaller stream. You know your area pretty well and can gauge what level the streams and rivers will be.”

But Mr Davies and Mr Hall agree that teachers often arrive with a different mindset. Back at school, they have been promoting the trip all year, encouraging pupils to sign up and collecting the money. They feel personally involved and “locked in” to what they have promised the kids they would be doing. “They think they have signed up to a specific activity,” says Mr Hall.

Arthog lies at the foot of Cader Idris, one of the highest mountains in Wales, yet groups rarely climb to the top.

“A foothills walk can be just as enjoyable,” says Mr Hall. “The whole experience of the outdoors is so alien to most of them, on a stormy day the kids will have just as much fun walking by the side of the (Mawddach) estuary.”

Coleham primary school in Shrewsbury certainly had lots of fun. In a split week last year, two groups of children enjoyed rock climbing, canoeing, mine excavation, gorge walking and a night walk. “I value the outdoor experience for the challenges it provides for the children. It can offer so many learning experiences,” says Diana West, Coleham’s deputy head .

Ms West climbs and rides a mountain bike, but she has never considered leading a group herself. “If there’s someone highly qualified and specialised, I’m going to use them. It’s about using people’s strengths.”

Ms West acknowledges that centres like Arthog are not the cheapest option.

That was part of the reason for going for three days instead of the full week. “We might be able to do something else or go for longer for the same money,” she said. “But you can’t match the quality of the experience.”

Or the peace of mind.

Arthog Outdoor Education Centre Tel: 01341 250 455; www.arthog.co.ukKilvrough Outdoor Education Centre - South WalesTel: 01792 232743Other licensed centres can be found on the AALA website www.aala.org