This study investigated the effect of a school-based ergonomic intervention on childrens' posture and discomfort while using computers using a pre/post test study design. The sample comprised 23 children age 9 and 10 years. Posture was assessed with Rapid Upper Limb Assessment (RULA) and a workstation assessment was completed using a Visual Display Unit (VDU) checklist. Self reported discomfort was also recorded at the beginning and end of the computer class. Following an ergonomic intervention that included education of the children and workstation changes, the outcome measures were repeated. There was a positive response to the intervention with significant changes between the pre-intervention and post-intervention scores for posture (p = 0.00) and workstation (p = 0.00). The change in discomfort scores from beginning to end of the computer class between the pre-intervention class and the post-intervention class was also significant (p = 0.00). The study highlights the need for continuing concern about the physical effects of children's computer use and the implications of school-based interventions. (Contains 4 tables and 5 figures.)