Bioethics is an increasingly important part of the biosciences curriculum at school and in higher education, but few science teachers have much experience of teaching the subject in an engaging or interactive manner. This article sets out a session that allows students to practise the skills of ethical thinking and ethical debate in a relevant context as members of an "ethics committee". They can then compare their decision with the opinions of the group as a whole as well as explore the resolution of the issue in the real world. The session can be easily adapted to a range of audiences, and has been trialled with primary and secondary school children, undergraduates in medicine and the biosciences, and adults as part of university outreach events. (Contains 2 tables.)