The study examines gender-related injury frequency by the type of school activity. Data were taken from an injury register created during the school year 1996/97 with the help of 79 Swedish public-sector schools. Injury ratios (IRs) by gender, type of municipality, and type of school were computed for injuries during all types of activities, for sports-related injuries, and for injuries sustained during recess periods. IRs were higher among boys for recess activities, and among girls for sports activities. IRs showed major variation by type of school, and minor variation by type of municipality. Schools catering for pupils aged 7-12 years had the highest IRs for all groups of injuries, both on aggregate and by gender. Gender-related injury-event occurrence at school clearly varies with kind of activity, but less so with age of pupils. The extent to which this reflects individual differences rather than varying exposure is uncertain.