Why Your Teen Can't Fall Asleep (It's Not Just Screens)

A lot of parents come to me worried about their teenager’s sleep. It usually sounds something like: they’re up half the night, impossible to wake in the morning, and it’s turning into daily arguments at home.

Both in my work and in conversations with parents I know personally, the assumption is usually the same — it must be the phone. And while screens are part of the picture, what’s actually going on is often more interesting, and more useful to understand.

The shift that’s happening underneath

During adolescence, the body clock naturally moves later. Melatonin is released later in the evening, which means most teenagers genuinely don’t feel sleepy until well into the night — and they still need a similar amount of sleep overall. When you combine that with early school start times, many teens are running on chronic sleep restriction. Not because they’re choosing to stay up. Because their biology and their schedule are pulling in opposite directions.

What looks like laziness or resistance in the morning is, in a lot of cases, exactly that mismatch playing out.

How sleep and mental health interact

Sleep and mental health are closely intertwined, and once one is off, the other tends to follow.

When a teenager isn’t sleeping well, you tend to see more irritability, lower tolerance for stress, more pronounced anxiety, and difficulty concentrating. But anxiety and low mood also make it harder to fall asleep. By the end of the day, when things go quiet, thoughts tend to ramp up — and that’s often exactly when sleep becomes difficult.

Sleep is rarely an isolated issue. It usually sits within a broader pattern, and that pattern tends to maintain itself unless something in it shifts.

Why focusing only on screens misses the point

Apps like TikTok and Instagram are often part of the picture, but they’re rarely the main driver. What I more commonly see is a combination of a delayed body clock, irregular sleep and wake times, overthinking at night, academic pressure extending late into the evening, and a general lack of physical movement across the day.

If the focus stays only on removing the phone, the underlying pattern usually stays in place.

What tends to help

What’s most effective is rarely a single fix. It’s usually a few consistent adjustments that cumulatively shift the pattern.

Fix the wake time first

A relatively fixed wake-up time — even when nights have been rough — does more to stabilise things than most people expect. Large weekend sleep-ins feel restorative but tend to push the body clock further back, which is why Sunday nights are often the hardest.

Create a buffer before bed

Most teens go straight from stimulation into bed. Sleep improves when there’s a transition period — something low demand and predictable that gives the nervous system time to wind down.

Address the racing mind earlier

If a teenager is lying in bed with a racing mind, the bed has become the place where the problem shows up, but not where it starts. It’s usually more effective to help them offload or organise their thoughts earlier in the evening, before they’re already in that space.

Take a collaborative approach to screens

Strict rules tend to escalate conflict without reliably improving sleep. It’s usually more productive to understand what role the phone is actually playing at night, and work towards limits that are realistic and will stick.

Morning light

Morning light is super effective. Even ten minutes outside in the morning can help shift the body clock forward over time. It’s one of those small things that tends to get overlooked but is worth building in.

When it’s worth looking more closely

Sleep difficulties are common in adolescence. But if you’re seeing ongoing difficulty falling asleep most nights, significant daytime fatigue, noticeable shifts in mood or withdrawal, or increasing school avoidance that seems linked to sleep — it’s worth getting some support. In those situations, sleep is usually part of a broader picture rather than a standalone issue.

A final note

Most parents try to solve this by focusing on bedtime. In practice, that’s often the hardest place to intervene. It’s usually more effective to look at the full pattern across the day — wake time, evening wind-down, and what’s happening with night-time thinking.

When sleep improves, things tend to shift in other areas too. Mood stabilises, stress becomes more manageable, and day-to-day communication gets easier. It’s worth taking seriously.

If you’d like to talk about what’s going on for your teenager, I’d love to hear from you.