If the Scottish Executive and the Westminster Cabinet want to do one thing to show their commitment to education, they should accelerate the reduction in class sizes throughout nursery to primary 3 and immediately start reducing sizes at all other stages of compulsory education.

Yet as evidence continues to mount that smaller classes can have a major impact, there is still little sign of paying anything other than lip-service to the aim. But teachers, parents and, most importantly, pupils would find that significant class size reduction would be the best present they could get.

However, we must be clear that the key word is “significant”. The evidence from the United States is that to be worth while the reduction has to be large. Research suggests that somewhere between 13 and 17 pupils is ideal and that this size of class has amazing benefits in terms of the quality and quantity of learning (much more individualised attention), heightened classroom participation and communication skills, enthusiasm for and initiative in reading, a noticeable decline in the number of disciplinary referrals, a rise in teacher morale (how we could do with that) and better parental involvement.

Lest it be thought that these benefits apply only in small schools and communities, this report is about a programme implemented and evaluated in New York.

Importantly, the American scheme goes beyond the youngest stages. Although the Scottish Executive Education Department claims that there is only evidence of effectiveness at the youngest ages, the evidence from the US is that there can also be improvements for older pupils. California, for example, is piloting a scheme to give funding to all schools that wish to reduce classes at grade 9 (S1-S2 level). Schools can receive $170 a pupil for each subject to implement it.

In a piece of esearch I carried out with more than 150 modern studies departments, approximately nine times as many principal teachers concluded that smaller class sizes would improve the learning experience for pupils as believed removing disruptive pupils was the key. Yet on this side of the Atlantic horizons are so low that no mainstream politician even dreams of suggesting that class sizes should be reduced to the levels suggested above.

Education Secretary David Blunkett has famously talked about Labour improving state schools to such a level that parents will not want to send their children to independent schools. Apart from those who see a “snob” value, the main reason is the perceived link between attainment and class sizes - and the smallest sizes are in the independent sector.

It would be churlish to suggest that an immediate commitment to class size reduction across the sectors would be free of problems. The US evidence points to three immediate difficulties. First, staff shortages have led some states to bring in unqualified teachers. Clearly, we would not want to return to those days.

Second, a shortage of classroom space. It would be easier to plan for this during a phase of rebuilding or renovation, but there is little evidence of that being done, even in Glasgow where every secondary school is undergoing major refurbishment.

Finally, money. There would be a cost, but not only has the Government a huge budget surplus (conservatively estimated at more than pound;11 billion), there is much evidence that this would be popular with the public and money could be raised through taxation (although it is perhaps idealistic to think that Labour would even contemplate that during a pre-election period).

However, a campaign urging significantly smaller class sizes and proper funding to achieve them would put “education, education, education” back on the priority agenda.

Henry Maitles is head of modern studies, faculty of education, Strathclyde University.