Picture three children you may have met this term.
The first is in reception. He cannot sit for carpet time. He rocks, hums, pokes the child next to him. When you remind him of expectations, his reaction seems outsized: a flash of anger, then tears. Five minutes later, he is calm again.
The second is in year 3. She appears attentive, eyes fixed on the board. But when you question her, she cannot recall the instruction you just gave.
The third is in year 6. Bright, articulate, but perpetually scanning for danger. He comes to see you because he’s worried about his upcoming SATs. They’re giving him a stomach ache, he says.
Different ages. Different presentations. Yet many teachers recognise a common thread: children who seem easily dysregulated, or unable to sustain focus in the way we might expect.
National data show rising levels of SEND. This is partly because we are diagnosing it more readily. But it is also partly because symptoms themselves – particularly of affective disorders, linked to later-life anxiety and depression – are on the rise.
In the keynote that I will be giving at the CST Early Years Summit on 21 April 2026, I explore a simple but powerful idea: the children are changing because childhood is changing.
I argue that brains are plastic. They develop in response to how they are used. Environmental change is not abstract; it shapes the physical architecture of the developing brain.
Brains are prediction machines
Moment by moment, our brains use prior knowledge to anticipate what will happen next, compare this with incoming information, and update accordingly.
Learning works best when the world is neither too predictable nor too chaotic. If everything is obvious, there is nothing to learn. If everything is random, the brain cannot detect a pattern.
Optimal learning sits in a “Goldilocks zone” between the two.
Young brains have little prior knowledge. For them, even relatively simple environments can feel unpredictable. That’s why young brains learn best from slow-paced, highly patterned, repetitive interactions. Over time, as knowledge builds, predictable things become too predictable, and naturally seek out more variety.
Modern childhood gives young children the exact opposite of what they need. Early childhood is getting more fast-paced and unpredictable. Dense urban soundscapes, crowded homes, unresponsive parents, and screen media packed with fast-paced narratives and intense sensory input.
When unpredictability becomes stress
When we cannot predict what will happen next, the brainstem activates stress systems designed to help us cope with uncertainty. In the short term, this can be adaptive. Heart rate rises. Attention narrows. We enter high alert.
But if unpredictability is frequent or chronic, this high-alert state can become the new normal . Behaviourally, this may look like hypervigilance, impulsivity, emotional reactivity or, conversely, shutdown.
I describe these as “brainstorms in the brainstem”: chain reactions where small triggers cascade into anger, fear and physiological arousal.
Over time, this hyper-reactivity can become turned in on ourselves, as stress becomes anxiety.
What does this mean for school trusts?
For trusts, this is not about abandoning rigour or lowering expectations. It is about strengthening foundations.
Increase predictability through rhythm and routine. If home life is intense and unpredictable, then schools need to give the opposite of that. Clear daily structures, consistent lesson formats, visual timetables and predictable transitions. Rituals at key points in the day can help children’s physiological systems prepare for what comes next.
Be child-led in calibration. Children used to being in a high-alert state at home may ‘seek out’ similar types of situation at school. Some behaviours that look disruptive may be attempts at self-regulation: rocking, humming, movement, deliberate provocation of staff and other children.
For trusts, this raises strategic questions. Do behaviour policies increase predictability, or inadvertently introduce uncertainty? How do we support staff consistency, especially amid staffing changes?
Strong foundations are built from stability, rhythm and relationships. If childhood is changing, our schools need to change accordingly. By understanding how brains learn, school trusts can design environments that are aligned with the rapidly changing needs of today’s children.
- Professor Sam Wass is a child psychologist and neuroscientist who studied at Oxford, London, and Cambridge. He leads the Institute for the Science of Early Years in East London.
- CST Early Years Summit takes place on 21 April 2026 in Birmingham.
We welcome perspectives from a diverse range of guest contributors. The opinions expressed in blogs are the views of the author(s), and should not be read as CST guidance or CST’s position.
