The purpose of this study is to examine the efficacy of the ADHD-Toolkit (a toolkit for school behaviour modification in primary school children with ADHD-behaviours) in terms of general improvement in ADHD symptoms, specific targeted school-related problem behaviours, other disruptive behaviour disorder symptoms, teacher attitudes towards ADHD, teacher-child relationship and child self-esteem.

Attention-Deficit/Hyperactivity Disorder (ADHD) is a debilitating and common disorder of childhood marked by pervasive and persistent patterns of inattention, overactivity and impulsiveness. It is associated with impairment in a range of domains at both home and school and leads to long term educational and vocational underachievement, delinquency and conduct disorder and social and marital problems. Current treatment approaches involve both pharmacological and non-pharmacological options. Non-pharmacological options tend to focus on home-based approaches such as parent training. These can be effective especially in limiting impairment and reducing symptoms of comorbid problems such as oppositional defiant disorder (ODD) and other psychiatric comorbidities. This can really improve the quality of life of children with ADHD. However, a major problem with these home-based approaches is that their effects are unlikely to generalise to the school setting. This means that to effectively treat ADHD and to deal with impairment at both home and at school one needs to supplement home based approaches with effective school based strategies.

Classroom-based approaches that have been tried with ADHD can be divided into two types (Pelham & Fabiano, 2008). First, there are classroom based management strategies where teachers manipulate the consequences of behaviour to reduce (i.e., negatively reinforce) inappropriate behaviours (aggression, loss of concentration, disruptiveness) and increase (reinforce) appropriate behaviours (compliance, concentration). The second type of intervention focuses on academic targets through manipulating the academic instruction and materials (i.e., reducing task length, peer tutoring). In the current proposal the investigators focus on the first category. Pelham & Fabiano (2008) recently concluded that "the evidence for BCM [behavioural classroom management] for ADHD was substantial".

However, while there is a considerable evidence base for the value of classroom management as a component of ADHD treatment in multi-modal psychosocial treatment packages in school-aged children, there is a lack of well designed randomized studies in a naturalistic school setting that can provide a definitive estimate of efficacy for such approaches.

At the University Hospital of Leuven a toolkit for school behaviour modification in children with ADHD has been developed and piloted. This is an instrument for teachers to systematically target specific behaviours in the classroom and the playground with the ultimate goal of improving school ADHD behaviours and reducing oppositionality. Teachers will identify the behaviours which are most challenging and apply a series of levels of intervention with increasing intensity of monitoring, feedback and training. The effect of a three month application of the toolkit will be evaluated compared to a waiting list control group. Outcome measures will include measures of ADHD behaviours, oppositional defiant behaviour, teacher attitudes towards ADHD, teacher-child relationship and child self-esteem.

Inclusion Criteria:

• The teacher must rate the ADHD symptoms of the student above or equal to the 90,9th percentile on the inattention or hyperactivity/impulsivity subscale of the VvGK (a Dutch translation of the Disruptive Behaviour Disorders Rating Scale).
• There is a maximum of 2 children per classroom that may be included.

Exclusion Criteria:

• None (Medication use would not be a reason for exclusion from the sample if children still fulfill the inclusion criteria)(Children with mental retardation (IQ < 70) will automatically be excluded from the study, since the study runs in normal schools.