ABSTRACT Rehabilitation aims to increase individuals’ ability to interact with their environment. Focusing on the paediatric context, rehabilitation is likely to optimise children’s development while improving and maintaining their functioning. However, children with neurodevelopmental disabilities, such as cerebral palsy, often show low engagement in rehabilitation sessions. This study aimed to assess the effectiveness of a narrative-based training program in increasing in-session engagement for children with cerebral palsy undergoing rehabilitation (i.e. targeting affective, behavioural, and cognitive dimensions). The study was conducted in three cerebral palsy rehabilitation centres and followed a one-group double-pre-test, one-post-test design. Fifteen children with cerebral palsy participated in the training program twice a week over nine weeks. The program aimed to promote children’s in-session engagement in rehabilitation through a story tool grounded in a self-regulation theory. Current data revealed the key effects of implementation time in the three dimensions of in-session engagement. Post-hoc tests of within-subjects indicated significant differences between pre-test 1 versus post-test and pre-test 2 versus post-test in the three dimensions of in-session engagement. This narrative-based intervention was a helpful tool promoting in-session affective, behavioural, and cognitive engagement in rehabilitation for this sample of children with cerebral palsy.