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Guide ยท ADHD

ADHD symptoms in kids: what it looks like at each age, and what to do

Most children are distractible and full of energy at times. ADHD is when that pattern is well beyond what is usual for a child's age, has lasted months, shows up at home and at school, and gets in the way.

Updated 5 October 2026 · About 10 minutes to read · All guides

In short

  • ADHD in a child is a lasting pattern of inattention, hyperactivity or impulsivity, well beyond what is usual for their age, that gets in the way at home and at school.
  • A diagnosis needs six or more symptoms from a list, lasting at least six months, present before age 12, in more than one setting, and causing real difficulty.
  • Australia's national child survey found 7.4% of 4 to 17 year olds had ADHD, about twice as many boys as girls.
  • Girls, quiet inattentive children and the youngest children in a school year are the ones most often missed or mislabelled.
  • Start with your GP. In Australia a child is usually diagnosed by a paediatrician, child psychiatrist or psychologist, using interviews, developmental history and rating scales from home and school.

What ADHD looks like in a child

ADHD shows up in two groups of behaviour. Inattention: losing track of instructions, drifting off mid-task, careless mistakes, lost jumpers and lunchboxes, forgetting everyday things, avoiding anything that takes sustained mental effort. Hyperactivity and impulsivity: fidgeting and not staying seated, running and climbing at the wrong times, not playing quietly, talking non-stop, blurting out answers, interrupting.

Every child does some of these. What separates ADHD is the pattern. The current diagnostic manual (DSM-5-TR) sets the rules, in plain words:

  • Enough symptoms. Six or more from either list. From age 17, five.
  • For long enough. At least six months.
  • Started early. Present before age 12.
  • More than expected for their age. Beyond other children at the same developmental stage.
  • In more than one setting. Home and school or friends, not one place.
  • It gets in the way. Real difficulty with learning, friendships or family life.
  • Nothing else explains it better. Not mainly defiance or misunderstanding.

As Healthdirect puts it, restlessness and distraction are natural from time to time; with ADHD they are persistent and interfere with daily life.

Signs of ADHD by age

The symptom lists are the same at every age, but they look different at four, nine and fifteen. The age bands and examples are ours; the symptoms come from the Raising Children Network, Healthdirect and the diagnostic criteria.

AgeInattention often looks likeHyperactivity and impulsivity often look like
Preschool (3 to 5)Flits between activities every minute or two, cannot follow a story to the end, does not seem to hear a simple instruction even when repeated.Climbs furniture, runs off in car parks, cannot sit through a meal or a mat session, grabs and pushes in, far more on the go than other children in the room.
Primary school (6 to 12)Homework that takes hours for twenty minutes of work, careless mistakes in work they can clearly do, "not applying themselves" on school reports, lost hats and notes every week.Out of their seat, fidgeting and tapping, talking over the teacher, calling out, trouble waiting their turn, acting before thinking.
Teenagers (13 to 17)Assignments started late or not at all, lost deadlines and belongings, disorganised study, a gap between ability and marks.Restlessness rather than running around, talking a lot, interrupting, impulsive decisions with money, friends or risk.

What is normal at each age

Raising Children Network says preschoolers are commonly very energetic, find being still and quiet for long hard, and struggle with long or complicated instructions, so a preschooler is compared with other preschoolers. School-age children are still developing self-regulation, patience and longer attention; school usually raises ADHD at this age because the demands to sit, listen and finish work climb each year. For teenagers, the criteria still require symptoms before 12: difficulties that began at 14 with no earlier history point elsewhere, such as anxiety, low mood or poor sleep.

ADHD in girls, and in quiet kids

ADHD in girls is more often the inattentive kind: distracted, disorganised, forgetful, daydreaming, chatty rather than disruptive. That is easier to overlook, and the Australian ADHD guideline notes that girls frequently go unrecognised or are diagnosed late.

A Swedish study of 19,804 nine-year-old twins looked at what predicted a clinical diagnosis. Boys scored higher on symptoms across the population, but among diagnosed children severity was similar in both sexes. The difference was what it took to get there: hyperactivity, impulsivity and conduct problems predicted a diagnosis and medication more strongly in girls than in boys. The authors concluded girls with ADHD may be more easily missed, and less likely to be prescribed medication, unless they have prominent externalising problems.

The Australian survey shows the gap: 10.9% of boys aged 4 to 11 had ADHD against 5.4% of girls; at 12 to 17 it was 9.8% against 2.7%. Quiet, inattentive boys are missed for the same reason. More in ADHD in women and girls and ADD vs ADHD.

How common ADHD is in children

The best Australian figure comes from the second national child and adolescent mental health survey (Young Minds Matter), which interviewed the parents and carers of 6,310 children aged 4 to 17. ADHD was the most common disorder found, with a 12-month prevalence of 7.4% (confidence interval 6.6% to 8.2%). Across all seven disorders measured, 13.9% of children met criteria for at least one.

Worldwide, a meta-analysis of 41 studies from 27 countries put the pooled prevalence of ADHD in children and adolescents at 3.4% (2.6% to 4.5%). Estimates vary with how each study is run and how strictly impairment is applied.

What causes ADHD, and what does not

ADHD is strongly inherited. Across 37 twin studies, the average heritability was 74%, meaning most of the variation between children is down to genes. It is polygenic: many common variants each adding a little, not one ADHD gene. What is ADHD covers the genetics and brain research in more depth.

Early biology plays a part too. Healthdirect lists smoking and drinking during pregnancy, premature birth and low birth weight as environmental factors, and the Australian guideline names children born preterm as a group at significantly higher risk.

What the evidence does not support

  • Sugar. A JAMA meta-analysis of 23 studies concluded that sugar does not affect the behaviour or cognitive performance of children.
  • Parenting. The ADHD Evidence Project, which curates the research behind the international consensus statement on ADHD, lists poor parenting among the myths about its cause. Parent training is recommended because it helps families manage ADHD, not because parents caused it.
  • Screens. A meta-analysis of 45 studies found only a small link between media use and ADHD-type behaviour, and the studies cannot show which way it runs. See the FAQ below.

Things that look like ADHD, or come with it

The Australian guideline says clinicians should take a full history and examination to find any medical cause for ADHD-like symptoms, and names sleep disorders, hearing or vision impairment, thyroid disease, anaemia and medication side effects as conditions that can mimic ADHD.

Hearing, vision and sleep

A child who cannot hear the teacher or see the board looks like they are not listening. Sleep disorders are on the mimic list too, and Healthdirect notes obstructive sleep apnoea is more common in people with ADHD. A tired child is a restless, irritable, inattentive child, so loud snoring or restless sleep is worth raising with the GP. The guideline also says sleep should be part of any lifestyle plan for ADHD.

Anxiety, and a hard time at home

Anxiety disorders are among the most common conditions alongside ADHD in children, and an anxious child can look inattentive because worry takes up attention. Children in out-of-home care are a high-risk group in the guideline, and the effects of family violence, neglect or a chaotic period can look like ADHD. Healthdirect notes the reverse too: most children with ADHD have not experienced early trauma.

Learning disorders and autism

Learning disorders in reading, writing or maths, and language disorders, often accompany ADHD and can be mistaken for it: a child who cannot decode the page stops trying, which looks like inattention. A cognitive and learning assessment can separate the two. Autistic children are at significantly higher risk of ADHD, and autism is among the most common conditions found alongside it.

Being the youngest in the class

A Western Australian study of about 311,000 children found that among 6 to 10 year olds, those born in June, the youngest in their school year, were about twice as likely to be on ADHD medication as those born in July, the oldest. A systematic review by the same group found the effect in 17 of 19 studies across 13 countries. Adults compare a child with classmates who may be nearly a year older, so if your child is one of the youngest, say so.

Getting assessed in Australia, and what helps

Who to see

Start with your GP. In Australia a child's ADHD diagnosis is usually made by a paediatrician, child psychiatrist or psychologist. The guideline does not restrict diagnosis to one profession, but only medical practitioners can prescribe, so if medication is a possibility a paediatrician or psychiatrist will be involved. Which doctors can prescribe for a child differs by state; see our child ADHD assessment page.

Rating scales

Standardised rating scales such as the Conners and Vanderbilt scales are a core part of the assessment. These are structured questionnaires completed by a parent and a teacher that score ADHD symptoms against other children the same age; the Vanderbilt is designed for ages 6 to 12. They inform the diagnosis but do not make it.

Medicare

Under 25, Medicare has a once-per-lifetime paediatrician assessment item (item 135) for a suspected complex neurodevelopmental disorder, and on that referral a psychologist's assessment sessions can attract a rebate (item 82000) in some situations. Ask about this before any appointment is made.

What helps

  • Parent and family training first for young children. The guideline recommends an ADHD-focused group parent-training program for parents of children under 5 with ADHD, and parent or family training for ages 5 to 17.
  • School adjustments. Under the Disability Standards for Education 2005, made under the Disability Discrimination Act, schools must make reasonable adjustments so a student with disability can take part on the same basis as others, in consultation with the student and family.
  • Medication where indicated. For children 5 and over, the guideline lists methylphenidate or dexamfetamine/lisdexamfetamine first, with atomoxetine or guanfacine if stimulants are not tolerated or do not work. Healthdirect says non-medicine approaches should be tried first in children and usually continue alongside, and lists reduced appetite, poor sleep, irritability and headache as common side effects of the stimulants. ADHD medication sets out the evidence and risks evenly.

If you are unsure whether an assessment is the right next step, our free screener (choose "My child") suggests which fits, and tells you if one does not look warranted. It is not a diagnosis.

Questions people ask

What are the signs of ADHD in a 5 year old?

A child far more on the go than others in the same room, who climbs, runs off, cannot sit through a meal, grabs and pushes in, flits between activities and does not take in simple instructions. What points to ADHD rather than normal energy is the degree, six months or more of it, at home and at kindy, causing real problems. For under-5s, Australia's guideline recommends parent training first.

How do I know if my child has ADHD or is just energetic?

Energy alone is not ADHD. Count the symptoms (six or more from a list), the time (at least six months), the places (home and school), whether it is well beyond other children the same age, and whether it is costing your child in learning, friendships or family life. Then ask whether poor sleep, hearing, anxiety or being the youngest in the class explains it. If several boxes are ticked, see your GP.

At what age can a child be diagnosed with ADHD?

There is no fixed minimum. The criteria require symptoms before 12, and Australia's guideline includes recommendations for children under 5, so preschoolers can be diagnosed. Many children are assessed in the early primary years, when school demands make the pattern clearer. Teenagers and adults can be diagnosed too, with evidence the symptoms began in childhood.

Does my child need medication for ADHD?

Not necessarily. For children under 5 the Australian guideline recommends parent training as the first step and makes no recommendation about medication. For children 5 and over, stimulant medication is one recommended option where ADHD is affecting the child's life, and Healthdirect says non-medicine approaches should be tried first and usually continue alongside. The decision is made with the prescribing doctor.

Can a child grow out of ADHD?

Some do, but fewer than parents are often told. In a 16-year follow-up study, 558 children with ADHD were tracked to an average age of 25. About 9% had a sustained remission, about 11% had stable ADHD throughout, and about 64% fluctuated between remission and symptoms returning. Over 90% still had some symptoms at least into young adulthood.

Is ADHD caused by too much screen time?

No. ADHD is strongly inherited, with heritability around 74% across twin studies; the other factors with evidence behind them are prenatal exposures and premature birth. A 2014 meta-analysis of 45 studies found a small association between media use and ADHD-type behaviour (a correlation of 0.12), and because the studies are observational they cannot show direction: a restless child may be drawn to screens, and screens can displace sleep, which does affect attention. Screen time is worth managing, but it is not why a child has ADHD.

Wondering whether an assessment makes sense? The free screener takes about three minutes, for your child, your adult son or daughter, or yourself. It suggests which assessment fits, and it will tell you if one does not look like the right next step. Start the free screener.

Related

Child ADHD assessment · What is ADHD? · ADHD symptoms in women and girls, and why they get missed · ADHD medication · Free autism and ADHD screener · All guides

Where this information comes from

We would rather you checked us than took our word for it. Every link below is the original source, not a summary of one.

Links to external sites are provided for reference. We do not control them and they may change. Last checked 5 October 2026.

This guide is general information, not medical advice. If you are worried about yourself or your child, talk to your GP.

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