Short-sleeping school-age children are at risk for poor mental, cognitive, and brain health. Alarmingly, in Singapore, 64.5% of school-age children sleep less than the minimum recommended duration of 9 hours on school nights. These short-sleeping children, on the other hand, spend on average 2.5 hours per school day on media use for non-academic purposes, revealing the potential of reducing their screen time for more sleep. The effectiveness of various interventions targeted at reducing media use and/or improving sleep has been studied among school-age children. While these existing interventions focus on screen use in the evening and before bedtime in view of the physiological effects of light emittance and the cognitively stimulating effects of the media content, they took a one-size-fits-all approach and ignored the individual differences in the duration, type, and purpose of media use throughout the day. In this project, we will use a scalable, personalised approach to curtail media use based on each individual’s need throughout the waking hours so as to (1) advance children’s bedtime and hence, increase their sleep duration, (2) improve their mood, depressive symptoms, and behavioural problems, and (3) enhance their brain and cognitive functions.