Good news can on occasion come out of a crisis. Under pressure to make significant cuts, the City of Glasgow has introduced airline-type trays for school meals in 30 primaries in the Junior Diner Club. And it seems to be cracking one of the major problems of the late 20th century in Scotland - inducing children to eat vegetables.

Instead of buying their meals in a cash cafeteria where they had complete freedom of choice as to what to buy, children choose one of three different trays of food, each of which costs 90p or a free ticket. Because vegetables or salad are part of each package, more of both are being consumed.

“It’s a real breakthrough,” says cleaning and catering services area manager Pamela Clark. “We used to try to encourage the children to buy vegetables but they didn’t want to spend the extra 9p on broccoli. Now they often eat vegetables because they’re on their tray.”

The system is a halfway house between the cash cafeteria and the old system of no-choice, take-it-or-leave-it school meals. On a typical day at one of the schools in the pilot scheme, Nitshill on the city’s south side, the children can choose between one cold and two hot meals.

The red tray has cold food - a sandwich, milk carton, yogurt or a piece of fruit, crisps and a piece of home baking. The green one has lamb and sausage pie, potato croquettes, green beans, fruit and home baking; and the blue one has turkey, gravy, boiled potatoes, sweetcorn, chocolate sponge and custard and fruit.

The last has the best nutritional balance, but Mrs Clark stresses that the first two, although imperfect, are also healthy choices.

“The children are a good way to eating well if they choose these trays, ” she says. “We don’t ban any food; we just limit its appearance. We think this is a realistic approach. In some schools you just don’t get children in unless chips are on.”

She cites fish and chips as an example of a less-than-perfect meal - it is fried - that still earns an occasional place on the menu because it is rich in nutrients. Staff fry the dish in polyunsaturated oil to make it healthier.

The cold meal is usually the most popular, partly because some children prefer not to use a knife and fork. On the day of my visit, 65 choose this meal, while 55 opt for the pie and 30 take the tray with turkey.

At first the system was rigid, but now children have a choice of sandwich or roll on their tray and sometimes pudding or fruit. Milk can be plain or flavoured and children can buy extras such as a cake or apple juice.

Even with this flexibility, the system is quicker than the old cafeteria. Children decide on the tray they want by looking at samples placed at the entrance, so they are not making up their minds at the service counter. Staff don’t have to read out the entire menu to the five and six-year-olds who can’t yet read. As pupils usually hand over a ticket or 90p, there is little messing about with different sums of money. Another time-saver is that staff no longer have to talk kids out of buying beetroot and chips or a trayful of cakes.

Under the cash cafeteria system there was more wastage, particularly of salad bowls, vegetables and vegetarian meals, which staff were required to prepare even though there were few takers. Now the salad is in a sandwich or is a side salad on the tray and is often eaten.

The reduction in waste, along with an increase in uptake in the pilot schools of 2 per cent among cash payers and 10 per cent among free-ticket holders, means the council is expecting savings in labour and materials of Pounds 100,000 per year (out of a Pounds 7 million budget) when the system is introduced to all Glasgow primary schools in August. There will be no compulsory redundancies but temporary staff will lose hours.

Five cartoon characters designed to appeal to older as well as younger children have been commissioned for decoration of dining rooms to promote the Junior Diner Club in Glasgow’s 206 primary schools.

Asked about the proposal of some cash-strapped local authorities to cut meals back to just a roll and soup, Mrs Clark says that, although this kind of meal can be nutritionally sound, she believes that in practice it would lead to a great drop in numbers taking school meals because of the boredom factor. Catering operations manager David Parry says: “In many homes there is not much money to put food on the table. For many children the school meal is their main meal of the day.”

Nitshill headteacher William Roddie says that the only problem he has had with the new system related to the tray colours in this football-mad city. He talked to the children and the boycott amounted to a two-day wonder.

One obstacle to further improvement in the numbers taking meals at Nitshill is competition from other caterers such as the nearby Community Centre where cheap chips are available. Another is that older children want to assert their independence and go outside at lunchtime, perhaps to play football which is not allowed in the playground.

Parents with little disposable income but earnings not low enough for their children to qualify for school meals are also motivated to prepare packed lunches rather than pay some Pounds 40 a month for school meals for two offspring. Children keen to eat comfortingly familiar foods may also be reluctant to give up their packed lunch.

The challenge for the caterers is to mass-produce meals that are irresistible to children, hours in advance. They will know they’ve cracked it when one of the children eats a Brussels sprout.