Children are vulnerable to disease, yet are poor at recognising and avoiding sickness. Thus, the current study aims to recruit 5- to 9-year-olds (anticipated 50% female, 60% White, 60% Hispanic/Latine) to test whether children's sickness perception is malleable and can be improved through training. We created developmentally appropriate stories and games for children, based on training methods that improve adults' sickness perception. We hypothesise that children randomly assigned to engage in the disease-prime training will, like adults, display more accurate sick face perception compared to participants in a control condition. If children do show improvements, this would suggest that their sickness perception is malleable. In contrast, if they do not show improvements, this may suggest an increase in malleability with age. Developing effective interventions for children's pathogen avoidance that account for the flexibility (or lack thereof) of children's disease detection systems may reduce disease transmission and improve public health.