Not long ago, I visited a school where the conversation unexpectedly turned to birth rates. The school had looked into how many children were born in their region in 2024 and realised something striking: within two or three years, they might need significantly fewer kindergarten classrooms. It’s part of a broader trend – one we’ve been seeing for years – and it was again confirmed by the latest national statistics.

In Belgium, just 108,150 babies were born in 2024 – the lowest number since the wartime year of 1942. For the fourth time in five years, more people died than were born. And yet, the population still grew. How? Through migration. In many countries today, population growth is no longer driven by births but by mobility.

At first glance, this may seem like an issue for pension or healthcare policy. However, education systems worldwide will increasingly feel the consequences, not just in one way. And I do mean worldwide: Several countries have very low birth rates, with some experiencing population decline. These include South Korea, Taiwan, Singapore, Ukraine, and many European countries. Some of the lowest rates are in East and Southeast Asia, where high living costs and other factors discourage larger families.

In these countries, fewer births today mean fewer students tomorrow. Not immediately – babies born this year won’t enter school until 2027 – but the demographic trend is already visible. Rural regions, where population decline is most acute, may soon see school closures or merged classrooms. That can be devastating, not just for schools but for entire communities. Meanwhile, in urban areas – often supported by younger populations and migration – student numbers may stay stable or even rise. This creates uneven pressure: shrinking schools in some places, overcrowded ones in others.

Migration has become a key driver of population growth and of diversity. The number of young families arriving in cities like Brussels has kept school enrolment figures from dropping. For schools, diversity in home languages, cultural backgrounds, and educational needs is here to stay. Investing in language support, cultural responsiveness, community liaisons, and parent engagement can no longer be framed as temporary initiatives. They must become structural elements of high-quality education.

Ageing populations bring another, often overlooked, challenge: the changing nature of the teaching profession. As veteran teachers retire, education systems must rely on a new generation to replace them. But the pool of younger workers is shrinking. Making teaching more attractive, supporting lateral entry, promoting lifelong learning, and retaining experienced educators will all be necessary. Teacher shortages won’t solve themselves – and in some sectors or regions, there may even be oversupply.

These demographic shifts call for long-term thinking. What will a declining student population mean for education funding models? How do we prevent rising inequality as shrinking enrolments and growing diversity collide? And what happens if some schools face half-empty classrooms while others overflow?

This is not the time for panic or short-term fixes. Demographic change is slow but relentless. The latest numbers aren’t a surprise—they confirm a trend that’s been unfolding for years. Those who act now can prepare better for tomorrow. Smaller, more diverse, and—with the right policies—hopefully, more equitable schools are possible.

While many school systems may contract, universities and colleges could experience the opposite. In some countries, the number of higher education students might temporarily rise before the demographic dip hits there, too. That, too, demands foresight.