Why We Can't Think in a Heatwave (And What It Teaches Us About Learning)

Like many people across the UK this week, I've found myself saying the same thing several times a day: "I just can't think."

At the time of writing, temperatures have climbed to levels that would have seemed almost unimaginable a few years ago in June. Classrooms are hot. Offices are hot. Homes are hot. Even relatively simple tasks seem to require more effort than usual.

What's interesting is that nobody is particularly surprised by this.

When the temperature reaches 35, 38 or even 40 degrees, we accept that performance will suffer. We understand that concentration becomes harder. We expect people to be less productive. We recognise that our brains and bodies are operating under different conditions.

Yet when it comes to learning, we often forget this principle entirely.

For years, I have worked with students who are putting in significant effort but still struggling to make progress. They complete the work. They attend the lessons. They revise for the tests. Yet somehow the understanding never quite seems to stick.

The assumption is often that they need to work harder.

But what if they are already working hard?

What if the problem is not effort at all?

One of the things a heatwave reminds us is that human performance is heavily influenced by conditions. When our brains are busy regulating body temperature, there is less capacity available for concentration, decision-making and problem-solving. Tasks that would normally feel straightforward suddenly feel demanding.

Learning works in a remarkably similar way.

When a student has gaps in their foundational knowledge, their working memory becomes overloaded. They are trying to process new information while simultaneously wrestling with concepts they don't fully understand. The result is cognitive strain.

From the outside, it can look like disengagement.

The student appears distracted.

They lose focus.

They stop contributing.

Sometimes they give up altogether.

But underneath, something very different may be happening. They may simply have reached the limits of what their current understanding can support.

As teachers, we see this all the time.

A student confidently answers questions in one lesson but seems completely lost in the next. A capable learner suddenly struggles with a topic that appears relatively straightforward. A child who was enthusiastic last week becomes reluctant to participate.

The temptation is to view this as a motivation problem.

Often it isn't.

More frequently, it is an understanding problem.

Somewhere along the way, a misconception has taken hold. A key piece of knowledge has been missed. An important connection has not been made. The learner is trying to build new understanding on foundations that are not yet secure.  For more insights you can check out this article: why knowing more changes thinking.

No amount of effort can completely compensate for that.

Imagine trying to build a second storey onto a house before the ground floor walls have been finished. Working harder doesn't solve the problem. The structure itself needs attention.

Learning is no different.

This is one reason why diagnosis matters so much.

Before we ask students to do more questions, complete more revision or spend more hours studying, we need to understand what is actually preventing progress.

Do they genuinely understand the underlying concept?

Can they explain it in their own words?

Have they developed a misconception that is now acting as a barrier?

Are they being asked to apply knowledge they have not yet fully secured?

These questions matter because effective teaching is not simply about delivering content. It is about identifying where understanding breaks down and helping learners rebuild it.

The best teachers do this instinctively. They ask questions. They probe thinking. They look for evidence of understanding rather than simply evidence of completion.

Unfortunately, this becomes increasingly difficult as class sizes grow, curriculum demands increase and teacher time becomes more stretched.

The result is that misconceptions can remain hidden for months, sometimes years.

Students continue working.

Parents continue encouraging.

Teachers continue teaching.

Yet the underlying issue remains unresolved.

This is why I have become increasingly interested in approaches that focus on diagnosis before intervention. If we can identify misconceptions early, understand exactly where knowledge gaps exist and adapt teaching accordingly, we can often unlock progress far more effectively than by simply increasing the amount of work a student does.

The lesson from this week's heatwave is surprisingly simple.

Performance is not determined by effort alone.

Conditions matter.

When the conditions are wrong, even highly capable people struggle.

Whether the challenge is extreme heat, cognitive overload, a knowledge gap or a deeply embedded misconception, the solution is rarely to simply try harder.

The solution is to understand what is getting in the way and address it.

Only then can genuine learning begin.