Visit our resource centre for useful information and helpful activities for parents, teachers and teenagers living with ADHD.
Estimates vary, both between and within different countries, but ADHD is one of the most commonly-diagnosed behavioural disorders in children and young people.
Studies in the UK suggest that ADHD occurs in an estimated 3-9% of school aged children.
This means that the average UK classroom will include at least one child with ADHD.
Studies in the United States report higher rates of ADHD, possibly due partly to the use of different criteria to diagnose ADHD in the US.
ADHD is more common in boys than in girls, by a ratio of at least three to one.
Up to two-thirds of children with hyperactivity disorders continue to have problems into adulthood.