We are in the final week of the summer holiday here in Flanders. Many parents, and even quite a few pupils, if they are honest, will say that the summer break is simply too long. It is a discussion that comes back with some regularity, and one I get called about every few months. And there are actually good arguments for it. During a long holiday, children and young people forget some of what they have learned, something known as summer learning loss, although this can differ quite a bit from one pupil to another.

This is why there is concern that such a long interruption may be particularly disadvantageous for children who have fewer opportunities at home to read, practise or have other learning experiences, in contrast to summers filled with experiences that can help build a lot of background knowledge. So, logically: shorten the summer holiday? Yes, but there is now also an argument for doing the opposite.

This weekend, I read this piece by the BBC, which more or less turns the question on its head. Perhaps the holiday does not need to be longer, but it may at least need to fall at a different time. The reason? It is getting too hot to learn.

The starting point for the BBC article is the past school year in the UK. In Scotland, the summer holiday starts earlier than in England and Wales. While Scottish children were already at home, many English and Welsh pupils were still sitting in classrooms at the end of June and for part of July. Or rather, that was the idea. During the heat, more than a thousand schools had to close or send pupils home early. For pupils sitting their GCSE and A-level exams at the time, the timing was particularly unfortunate.

The BBC looked at British temperature data and found that in the 1960s, the first day of the year to reach 30°C occurred on average on 13 July. In the 2020s, that has shifted to 19 June. The UK Met Office now even talks about a lengthening de facto hot season, with more hot weather in May and September as well as during the traditional summer months. And importantly, heat also affects learning.

Research has linked high temperatures to poorer learning outcomes. A recent analysis by the UK Department for Education, based on work with the Met Office and University College London, cautiously estimates that the equivalent of 6.7 learning days per year may already be lost because of higher temperatures. With 2°C of warming, this could rise to 8.2 days. Note: these are estimates of learning lost, not eight days on which schools would literally be closed.

Heat also seems to play a role when pupils take tests and exams. Quite recognisable, by the way. The BBC piece refers to the recent Well-Adapted UK report by the Climate Change Committee. It states that pupils taking an exam at 32°C would have about a 10 per cent lower likelihood of passing than pupils taking the same exam at 22°C. Be careful here: this is a correlation, not demonstrated causation.

This suddenly makes the discussion about the summer holiday a lot more difficult. We often talk about what children lose because they are not at school during the summer. But it is also important to consider what children lose by being at school during the summer. Especially if the buildings are not adapted to the heat.

To be clear, the title of this post was deliberately a little provocative. But when I look at the UK and at where I live, I see a similar problem: old school buildings without climate control. Better shading, ventilation, insulation and perhaps cooling will probably become more important than ever. I know readers of this blog in the US and elsewhere will now shake their heads in disbelief.

One parent in the BBC article points out that during a heatwave, a properly cooled school could actually be a better place for some children than their home. Not every family lives in a house or flat that can cope with extremely high temperatures. Quite a few people discovered this during this summer in Europe.

Another possibility is not to make the summer holiday longer or shorter, but to move it. In England, there are now calls for the summer break to start earlier, as it already does in Scotland. Children could finish school at the end of June and return earlier in August. You keep the same number of school days but try to schedule them at times when conditions are better.

Here in Flanders, the summer holiday already starts on 1 July. But if hot periods like the ones we experienced this summer keep starting earlier, you could even ask whether that will be early enough in the future. And then I immediately think of all those poor university students sitting their exams in June in overheated rooms. While having to study in even more overheated bedrooms…

At the same time, moving the calendar may simply move the problem as well. Extreme heat can occur in May too, and increasingly in September. Anyone trying to design the school calendar of, say, 2050 on the basis of today’s weather risks falling behind the facts all over again.

But the discussion about the summer holiday has definitely become a lot more complicated.