Noreen Wetton, co-author of the national Health for Life primary school curriculum, said: "It's very scary for children and very tough for teachers, because there's just so much uncertainty about CJD."
Her comments came as the BSE scare continued and local authorities decided to have beef taken off the menu in hundreds more schools - ignoring government assurances that children are not at greater risk than adults of contracting CJD (BSE's human equivalent).
Mrs Wetton, a former headteacher who has spent more than a decade as a project leader in the health education unit at Southampton University, added: "You can tell children that if they're sensible in the sun they shouldn't get skin cancer, that if they don't smoke they shouldn't get lung cancer; but what can you say if they ask, as my six-year-old grand-daughters have asked me: 'Am I going to get mad cow disease?' "The risks just aren't quantifiable to the same extent as with other illnesses. There are no hard and fast answers that teachers, or indeed parents, can give, which makes it uniquely difficult. "
"I think the best approach is a pre-emptive one. Whether children are four or 14, teachers should ask what is worrying their pupils about BSE and then attempt to provide some answers, rather than giving out scientific information in a didactic way."
Although Health Secretary Stephen Dorrell told the Commons on Monday that "there is clearly no reason for the Government to advise local education authorities to remove beef from school menus", the list of councils banning beef has lengthened daily.
Major catering firms reported that beef was no longer being offered in the majority of the schools they serve, but some authorities, including Lancashire, Hampshire and Stockport, are allowing it to remain on offer in secondary schools, where they feel pupils are old enough to make up their own minds about the CJD risk.
Barbara Coupland, marketing director for CCG Services, said beef was no longer served in more than half of the 1,700 schools the firm supplies in England and Scotland. BET Catering, which provides meals for 3,000 schools in 11 authorities, said only three of its client councils had not banned beef. Both firms said they were buying in more lamb, turkey and other meats.
Further education colleges are reviewing the use of beef by catering students. Chris Crossley, head of catering at the London College of Further Education, in East Ham, said: "Our students have little faith in the safety of beef, and as a result of the latest publicity we have stopped preparing beef recipes."
A spokeswoman for Eastleigh College, in Hampshire, said its 200 catering students would continue to cook with British beef steak until instructed otherwise by local environmental health officers, but were no longer using beef offal or products which might contain offal.
Most schools will probably be relieved to have the risk eliminated from their canteens. Chris Davis, chairman of the National Association for Primary Education and head of Queniborough primary, in Leicester, where a county council beef ban has been in place for several years, said: "From a personal point of view, I would be very unhappy to be in a school that continued to serve minced beef products.
"There are parents in this area who are beef farmers and they are in dire straits because of the current situation. But you just can't take chances with children's health."
Nigel de Gruchy, general secretary of the National Association of Schoolmasters Union of Women Teachers, said: "Now that we know the initial scientific evidence was wrong and that there is a small risk involved in eating beef, taking it off school menus is the only sensible decision."
But Peter Davies, head of Bower Park secondary, in Havering, East London, where brightly coloured seats and fast-food-style service make the canteen resemble a burger bar, said the national reaction "seems like panic".
"Havering Council took beef off the menus last week, but if it were up to me we would have continued serving it until more scientific evidence emerges. We would always respect the decisions of individual pupils on what to eat, but I would much rather have waited a while, not least because we should not be teaching children that panic is a good way of reacting to a difficult situation. But mad cows are not high on the list of playground topics. Our pupils are still talking about Dunblane."