Researchers who involve children in their research are faced with the challenge of choosing between differing theoretical approaches which can prioritise children’s autonomy rights or their ‘vulnerability’ and their need to be protected. Somewhat confusingly, ethical guidelines seem to reflect a combination of these approaches. Even when researchers have settled on their preferred approach, they may find that this then has to be modified in accordance with gatekeeper requirements. In the context of children’s involvement in a child safety online project, this paper highlights the difficulties encountered because of a tension between children’s autonomy rights, educational norms in a school setting and child protection concerns and considers whether an appropriate balance was achieved.