Nearly four decades after free school milk ended, the Government has decided to give an apple a day to about 20,000 schoolchildren to protect their health.

Health Minister Annette King and Prime Minister Helen Clark announced the scheme yesterday as part of the Government's Cancer Control Action Plan.

That plan involves spending an extra $40 million a year on prevention and treatment of the disease and on palliative care for the dying.

Handing out apples, plums and other seasonal fruit from July is intended to protect children's health and foster more healthy eating habits at school and at home.

About $2 million has been earmarked for the scheme, which at roughly 50c for the fruit, will provide one piece to around 20,000 children each school day.

It will focus on primary and intermediate schools mostly in poorer areas and with high health needs, including those with higher concentrations of Maori and Pacific pupils.

To qualify, a school must first set up a health-promotion programme - overseen by district health boards - to encourage the school's wider community to improve their diet, increase physical activity, protect themselves from the sun and give up smoking.

Health Ministry spokesman Don Matheson said health deficiencies could also involve children who came to school hungry or did not have access to fruit at home.

All schools could join the health-promoting schools programme - 400 have already signed up - but not all would want free fruit. The $2 million would provide fruit for about 140 schools.

"If a school feels children have got plenty of access to fruit from home, that may not be the problem it is in some areas. It's not a one-size-fits all."

Health authorities say a diet rich in fruit and vegetables - the recommended minimum is at least five servings a day - combined with sufficient physical activity help to protect against obesity, diabetes, cardiovascular disease and cancer.

A national survey in 2003 found that 43 per cent of children eat less than the recommended daily three or more portions of vegetables and 57 per cent consumed less than two portions of fruit.

The free fruit scheme is based on a Massey University pilot study in Auckland - and a similar programme in Britain - which gave one piece daily to children at 10 schools and compared them with 10 other schools where no fruit was given.

More than 40 per cent of the children ate no fruit at the start, which reduced later to 22 per cent at the free-fruit schools. As fruit consumption rose, pie consumption declined - a trend that reversed when the free fruit stopped.

The researchers said teachers reported "greater alertness and concentration" in the children. No fruit was discarded but some children gave theirs to another child.

Sandy McCallum, principal of Mt Cook School in Wellington, said it was becoming a health-promoting school and would apply to join the free-fruit initiative. The school already provided breakfast or lunch for a few children who came to school hungry or without food.

Act health spokeswoman Heather Roy said the new $40 million was an "election-year reaction". But with too much of it going on cancer prevention and only $5 million on cancer treatment, too little would be done to reduce treatment delays.

Dr Robyn Toomath, of the Fight the Obesity Epidemic group, said free fruit was a great idea, "but it should go to all schools".

* The first Labour Government introduced free school milk in 1937. It offered children half a pint (284ml) of milk daily. Keith Holyoake's National Government scrapped the scheme in 1967 to save money.

Fruit in schools

Total cost: $2 million

Cost per piece of fruit: 50c

Number of children: 20,000

Number of schools: 140