Sexuality and humour share a fraught relationship at school, so that how humour might be productively employed in sexuality education constitutes a "risky" consideration. This paper explores the role of humour in sexuality education as observed in a Year 9 New Zealand health class. Adding to existing literature emphasising students' use of humour at school, it also considers how teachers might productively mobilise humour in the classroom. Findings reveal that while humour serves established purposes for students such as consolidating heterosexual masculinities, securing peer group hierarchies and disrupting learning agendas, it may hold other pedagogically productive possibilities. Potential uses include the relief of monotony, engaging with the needs of particular cultural groups of students, reinforcing taught information and reducing apprehension around potentially uncomfortable topics. Via this empirical exploration of the mobilisation of humour, the paper endeavours to open its potential as a conceptual site of possibility in sexuality education.