School trips can be among the most popular and enjoyable events in a young person's life, but they could become a thing of the past if a teaching union gets its way.

The NASUWT has advised its 223,500 members to avoid school trips following a series of court cases over accidents involving children.

The union fears its members could face prosecution if children in their care suffer injuries while on trips away from school.

One teacher, Paul Ellis, is serving 12 months in prison after pleading guilty to the manslaughter of a boy, aged 10, who drowned during an outing to the Lake District.

And cases such as those of teenagers Hannah Black and Rochelle Cauvet, who drowned while on a river walk in the Yorkshire Dales, have prompted calls for greater attention to the risks of outdoor activities.

According to the union, at least one child has died on a school trip each year over the past decade, with many more near-misses.

General Secretary Eamonn O'Kane said the decision was "highly regrettable" but necessary because society was becoming "increasingly litigious". He said: "Some have lost their jobs as a result of alleged misjudgements. "In an increasingly litigious society, which no longer appears to accept the concept of a genuine accident, our first responsibility must be to protect our members' interests."

Headteachers in Oxfordshire have rejected the call for teachers to boycott school trips, saying they form an important part of students' education.

Nicholas Young, headteacher of Wheatley Park School, near Oxford, said: "School trips are a good thing because they give young people an opportunity to have new experiences and to develop themselves as people. "There are obviously risks with any activity and I have sympathy for the NASUWT's position because society is becoming increasingly litigious, but I would be very reluctant to see our trips abroad or to outdoor centres or to battlefields in France and Belgium cancelled."

Any school wanting to have a trip involving pupils has to carry out a risk assessment. Once this is complete, Oxfordshire County Council will insure the trip to cover the school for accidents, but the insurance cannot protect teachers from criminal prosecution if they are found to be negligent.