Public science events are valued primarily as sites of individual learning. We explored the individual and collective value of university-based science events discussing climate change and motivations to attend. While events were most commonly valued as opportunities for learning, their social context created collective value associated with the physical gathering of like-minded people. Participants despairing at inaction on climate change were given agency through learning, participation, interpersonal discussions and normalising new behaviours. Post-event interpersonal discussions increase the reach of events beyond “the choir”. These discussions increase the diversity of messengers, creating opportunities for new framings and understandings of climate change.