This is one of several measures suggested by the Scottish Executive in a consultation paper on children's oral health, issued this week.
The paper says schools need to play their part in the drive to improve Scotland's notoriously poor dental hygiene record. Despite initiatives such as health-promoting schools, free fruit schemes, school meal offensives and breakfast clubs, more needs to be done.
"The unpalatable fact is that virtually no progress or sustained improvement in our youngest children's oral health has been achieved since 1991 when a target was first set. Radical steps are needed now if present and future generations of Scottish children are to avoid the legacy of poor teeth."
Malcolm Chisholm, Health Minister, commented: "At five years of age, 55 per cent of children in Scotland have dental decay. I am determined to address this challenge."
A target was set a decade ago that 60 per cent of pupils entering primary school should have no cavities, fillings or extractions by 2000. Little progress was made and the target was rescheduled three years ago for 2010.
The consultation document, which urges the controversial step of adding fluoride to the water supply, represents the first stage in the Executive's latest plan. It includes:
* Warnings in tuck shops against the damage to teeth from fizzy drinks.
* Encouraging schools and other places used by children to sell low-sugar fruit drinks in preference to fizzy drinks.
* Water coolers such as those Glasgow family learning centres have at the entrance to their buildings.
* Toothbrushing schemes in schools, including the use of fluoride toothpaste.
* More fresh fruit initiatives.
* More consistent health information spearheaded by the Health Education Board for Scotland.
The Executive believes that new community schools, with their emphasis on linking education, health and social work, could begin to turn the situation round.
In the meantime, ministers have suggested another target. By 2005, all children should receive dietary advice and support to improve their oral health and have used or been offered dental services before they start primary school.