It is hard to believe any child in this country has to go to school hungry yet some do. Teachers in low-income areas attest that pupils regularly turn up having had no breakfast.
It is hard to believe because a bowl of cereal and slice of toast do not cost very much - and for that same reason a political solution seems cheap. The Labour Party estimates it would cost between $3 million and $19 million a year to ensure every child in deciles 1 to 3 had one good meal a day.
The lack of precision in that estimate, however, is a warning. The cost might be as low as $3 million if, as party leader David Shearer believes, not every child in its favoured deciles would want or need the free meal. A government could not safely budget on that assumption.
Once parents realised that the school was providing breakfast, more would take advantage of it. In some cases their children might prefer the food at school, or line up there for a second breakfast. Parents of children at other schools, with slightly higher deciles, would begin to ask why they were missing out.
If school meals are introduced as a national education programme it will be difficult to contain the cost. Quite apart from the pressure to make it available for children of all taxpayers, there would be constant demands to improve it.
Nutritionists would be forever urging additions and improvements to the fare and they would quite likely come to see the meal as an opportunity to ban less wholesome lunch snacks that many pupils are inclined to bring to school.
Before long, the school meal could cease to be an option for all and become the only food permitted in the name of early intervention against obesity. Possibly that would be a good purpose but it is one that ought to be made clear at the outset, alongside the likely costs.
If school meals are proposed for the more limited purpose of poverty relief, Labour should also suggest a way to ensure the scope and costs of the programme can be contained.
One way of doing this was illustrated in the Far North last summer when Social Development Minister Paula Bennett went around promoting discussion of child abuse.
A worker from the Te Aupori Maori Trust Board told her it had been providing lunch for 15 to 20 children at five schools in its district. But it had been ordered to stop because food was not among the social services it had been contracted to provide for local schools.
Clearly the board's social workers had found that feeding those pupils was the best use of the money. We can be confident they could have put the grant to many other good uses and would have spent no more on providing school meals than was strictly necessary.
Those are exactly the judgments that people on the spot can make, and have to make when their funding depends on results.
Quite a number of undernourished children are already provided with meals in schools.
Last month, an advisory group to the Children's Commissioner praised a scheme being run by the KidsCan charity providing three food items daily in 223 low-decile schools.
Some other schools have raised private sponsorship to provide hungry pupils with some sustenance.
A simple breakfast is not much to ask and it should be provided for all children who need it. But if it is to be fully public funded, the food should be distributed by agencies that know a community and know who really needs help.