This report examines whether left or right-handedness effects early child development. Data on nearly 5,000 4 and 5 year old children from the Longitudinal Study of Australian Children were studied, using eight measures of child development, covering learning, social, cognitive and language aspects, as well as controlling for differences in socio-economic and parental characteristics. The analysis found evidence that left-handed children do significantly worse in nearly all measures of development, with the relative disadvantage being larger for boys than girls. Furthermore, the analysis found that left-handed children spend significantly less time each day on educational activities than right-handed children, and significantly more time watching television. This report shows that handedness differentials are evident even in early childhood.