TreeHouse School is for pupils with autistic spectrum conditions. All pupils have a statement of special educational needs. Many have learning difficulties, including speech, language, communication and sensory needs. Almost all pupils have difficulties in behavioural, emotional and social development. Pupils come from a wide geographical area in London and beyond. Around 90% of pupils are male. Pupils of minority ethnic heritage make up just over half of the school population. The proportion of pupils who are eligible for the pupil premium (additional government funding) is around twice that of schools nationally. Local authorities do not currently pass this funding onto the school. The school shares its purpose-built building with the charitable trust, Ambitious about Autism, which is the proprietor of the school. The school bases its work on the principles of Applied Behaviour Analysis (ABA) and, as well as teachers, ABA tutors work very closely with pupils to support learning. The school has been awarded Autism Accreditation annually since 2004. The school does not use other organisations to provide training but does makes use of links with other schools and businesses to give students wider learning experiences away from school. These activities are fully supervised by TreeHouse staff.