ADHD can present differently depending on a child’s developmental stage. Some children show clear signs during the primary school years when classroom expectations increase, while others begin to struggle later when academic, organisational and social demands become more complex.
Understanding how ADHD may appear at different ages — and how factors such as puberty and hormonal changes can influence symptoms, particularly for girls — can help families decide whether an assessment may be helpful.
Signs of ADHD in Primary School Children
In the primary school years, ADHD often becomes more noticeable because children are expected to sit still, follow instructions and sustain attention for longer periods.
Common signs may include:
- Difficulty maintaining focus during class activities
- Frequently losing school materials or forgetting instructions
- Trouble completing tasks without reminders
- Fidgeting, restlessness or difficulty remaining seated
- Interrupting others or speaking out of turn
- Behavioural challenges when bored or required to sit still
- Homework taking significantly longer than expected
- Emotional frustration when tasks feel effortful or overwhelming
Children with ADHD are often curious, energetic and capable, but may find it difficult to consistently organise their attention and behaviour within structured learning environments.
Signs of ADHD in Adolescents
As children move into adolescence, ADHD symptoms often shift in presentation. Overt hyperactivity may reduce, while challenges with organisation, planning, time management and motivation become more prominent.
Teenagers with ADHD may experience:
- Difficulty keeping track of assignments and deadlines
- Procrastination or delaying tasks until the last minute
- Problems organising school materials or managing study schedules
- Feeling overwhelmed by larger projects or exams
- Forgetting commitments or appointments
- Increased frustration, irritability or emotional reactivity
- Declining academic performance despite strong ability
- Adolescents with ADHD may have particular difficulties regulating their social media use and screen time, and can become particularly dysregulated when asked to do so.
- Drug use and risky or impulsive behaviours can also be higher in young people with ADHD.
Because secondary school requires greater independence and executive functioning, these challenges can become more noticeable during high school.
ADHD in Girls and Young Women
ADHD in girls can be under-recognised, partly because symptoms may present differently from the more disruptive hyperactive behaviours commonly associated with ADHD in boys.
Girls are more likely to show inattentive or internalised symptoms, such as:
- Daydreaming or appearing mentally “elsewhere”
- Difficulty sustaining focus during lessons
- Disorganisation and forgetfulness
- Quiet disengagement from tasks
- Struggling to keep up with schoolwork despite effort
Because these behaviours may appear less disruptive in the classroom, they are sometimes interpreted as anxiety, perfectionism or low confidence rather than ADHD.
As a result, many girls are not identified until late primary school, adolescence, or even adulthood.
The Impact of Puberty and Hormonal Changes
Hormonal changes during puberty can significantly influence how ADHD symptoms present for girls and young women.
Fluctuations in hormones such as oestrogen and progesterone affect brain systems involved in attention, emotional regulation and executive functioning. For some girls, these hormonal shifts can lead to changes in ADHD symptoms during early adolescence. For this reason, onset of ADHD symptoms
Parents may observe:
- Increasing difficulty with focus and concentration
- Greater emotional sensitivity or mood fluctuations
- Feeling overwhelmed by school demands
- Reduced tolerance for stress or frustration
- Increased fatigue or mental exhaustion when trying to concentrate
Many girls who previously appeared to be coping in primary school begin to experience more significant challenges during early to mid-adolescence, when academic expectations, social pressures and hormonal changes occur simultaneously.
Some young women also notice that attention and emotional regulation may fluctuate across the menstrual cycle, with symptoms sometimes becoming more pronounced during certain phases.
Because of these developmental changes, ADHD may become more visible during adolescence even if earlier symptoms were subtle or masked by strong effort and coping strategies.
When an Assessment May Be Helpful
Families may consider an ADHD assessment if attention, organisation or emotional regulation challenges are:
- Affecting school performance or learning
- Creating frequent stress around homework or study
- Leading to increasing frustration or overwhelm
- Impacting confidence, friendships or wellbeing
A comprehensive assessment helps clarify whether these patterns are consistent with ADHD, anxiety, learning differences or other developmental factors, and provides guidance on appropriate supports.
Supporting Strengths as Well as Challenges
Many children and adolescents with ADHD also demonstrate valuable strengths, including creativity, curiosity, problem-solving ability and high levels of energy and enthusiasm.
Assessment aims not only to identify areas of difficulty, but also to understand a young person’s strengths, learning style and support needs, helping families, schools and clinicians work together to create an environment where they can thrive.