PURPOSE: The aim was to examine widely used assessments within the rehabilitation of school-aged children with acquired brain injury (ABI) with the International Classification of Functioning, Disability and Health (ICF) as a framework. METHOD: A survey identified the assessments most widely used in the rehabilitation of school-aged children with ABI in Sweden. The aims of these assessments were linked to the ICF according to previously published linking rules for clinical assessments. RESULTS: Thirty out of 43 widely used assessments were linked to body functions. The remaining assessments were linked to activities and participation, with no assessments being linked to environmental factors. Many categories within activities and participation were missing, whereas some categories within body functions were covered by numerous assessments. CONCLUSIONS: The widely used assessments within paediatric brain injury rehabilitation do not cover essential aspects of functioning and disability. Specifically, assessments focussing on many crucial categories of activities and participation, and all categories within environmental factors were missing. A better understanding of school-aged children's health and disability might be achieved by using the ICF to identify a set of assessments, illuminating body functions, activities and participation and environmental factors.