Studies on Kenyan and Ugandan primary schoolchildren's knowledge of medicines and self-treatment practices show that children aged between 10 and 18 years have a broad knowledge of herbal and biomedical remedies and that they use them frequently, often without adults' involvement. They use pharmaceuticals, including prescription-only drugs, but lack knowledge about indications and dosages. There is a gap between the children's life worlds and the school health education as it is presently designed and taught in Kenya and Uganda. It limits itself to disease prevention and health promotion, and does not teach treatment or medicine-use. Self-treatment based on insufficient knowledge poses a threat to children's health and to the health of the wider community. Therefore, education on the critical and appropriate use of medicines needs to be developed and tested for possible use in Kenya, Uganda and other countries in which home-treatment is common. The proposed education on medicines should go beyond providing information on accurate dosage and indication: it should create critical awareness with regard to medicine-use, enabling children to use them appropriately and cautiously. Kenyan and Ugandan primary schoolchildren are active agents within pluralistic medical fields. By taking the children seriously as competent health care agents, the dangers of self-treatment could be reduced, and the potential of children could be guided to fruitful use. Educational interventions cannot solve the problems of self-treatment, which are related to the wider social and economic context, but they could contribute to increased awareness as a necessary condition for change.