This study adopts an experimental design to investigate the effectiveness of a password hygiene training programme. The password hygiene training programme adopted the Protection Motivation Theory's framework in its development, and was delivered online to 84 students aged 13 to 16. Strength of password measures, such as time taken, and number of tries required, to crack the password, were administered pre and post intervention. The findings revealed that the password hygiene training programme was effective in changing actual password setting behaviour. This study also provided hints on which perceptual changes, based on the theory's framework, was most influential in the exercise.