Les Bleus won the football World Cup this summer, and the French deserve our congratulations. But so too do at least two other countries – Croatia, the beaten finalists, and the Belgian Red Devils, the top-scoring third-placed team that played the most fluent and attractive football throughout the competition. These teams have reached the upper echelons of world football, despite having very small populations and therefore smaller talent pools. How did they do it? One aspect of Belgium's recent rise to global football giant has wider implications for how we think about education.

Belgium's "golden generation" of footballers is no fluke, but the outcome of an innovative selection and training programme. One of the key factors in the Belgian youth football model was the realisation that relative age bias led to many talented young footballers being ignored by scouts and coaches. In the early 2000s, the pioneers of the current Belgian football development model recognised that those born within the first half of a year were much more likely to make it to the top because of selection and opportunity bias. 40 per cent of the country's elite youth players were born in the first three months of the year, while only a fraction of those born in the final months of the year were emerging through the system. Of course, talented footballers are not born only from January to March. Rather the increased strength of the older children eclipses the talent of their younger counterparts. When players are young, physical strength may make a greater difference on the field than talent.

To compensate for this age bias, Belgium's youth football coaches developed the model of parallel teams: within each age group, there was a separate side for children born in the first and the second half of the year. They also created groups for those players who might develop their talent later than average, so that these players had equal chances to impress. Football scouts could focus on players’ competences and better detect their long-term potential rather than judge their immediate match performance. All of this was based on strong research evidence.

While Belgium has addressed age bias in football, like most other countries it has not acknowledged the issue in its education system – where it has more serious consequences. Indeed, research shows that younger children in a year group are at a disadvantage compared to their older peers – especially during the early years of primary school. Belgium is one of the countries where grade retention is commonly practised, and younger children are therefore exposed to a higher risk of repeating school years simply by virtue of being born towards the end of the year. Even in countries where grade retention is not a widespread practice, older children have an advantage in the learning process – particularly in mathematics and science.

Most school systems are organised around year-of-birth groups. This principle allows age bias to have a significant impact, as there can be up to 12 months difference between children in a typical class. This bias may play out in subtle ways. For example, younger children in a class may wrongly be considered by teachers as less "intelligent" – rather than just younger – and then receive less encouragement. This means that a significant proportion of children do not have the opportunity to fully develop their talents. Moreover, this bias may combine with other socio-economic and gender factors to reinforce problematic educational approaches and outcomes. As Malcolm Gladwell explains in his book "Outliers: The Story of Success", an initial advantage to older children often persists for years, creating patterns of achievement and under-achievement that are difficult to break.

So is it time to apply Belgium's approach to football in the classroom and split classes into 6 month age groups? This would reduce the ability range within classes and allow teachers to adopt more effective "whole class" approaches.

Alternatively, why not create classrooms with children from several year groups working together – just as they do at home in many families? Such an approach, based on developing children's natural curiosity and respecting the different stages of individual learning (rather than assuming that everyone should learn the same things at the same time), has proved to be successful in early years education, with the work of Céline Alvarez in France being inspirational and a catalyst for significant reform. So why not extend these organisational principles into primary education?

Perhaps the lesson we should learn from this summer's World Cup is that we all have talent, and we can't afford to waste it. If we persist in organising schools in a way that doesn't allow all children to fully develop their talents, we are doing a major disservice to children and to society.

Authors: Ralitsa Donkova and David Crosier