AIM:Some children's special health-care needs (SHCN) are formalised at the start of schooling (established SHCN), but a larger proportion start with difficulties that are milder or not yet diagnosed (emerging SHCN). This study explores whether: (i) the prevalence of teacher-identified SHCN (both overall and according to type of needs) and (ii) distribution across disadvantaged communities have changed over three successive population cohorts of Australian children. METHODS:We draw on repeated cross-sectional data from the Australian Early Development Census, a teacher-reported checklist completed on full populations of Australian school entrants in 2009, 2012 and 2015. It includes a measure of SHCN, as well as demographic information. RESULTS:The proportion of children with emerging and established needs was mostly stable from 2009 to 2015 (emerging needs: 17.1-18.9%; established needs: 4.4-4.9%). Change over time was observed in the prevalence of some specific types of impairment. Speech impairment rose by 14.7% for children with emerging needs, and emotional problems rose by 13.7% for children with established needs. Children living in the most disadvantaged neighbourhoods had higher odds of SHCN in all years (e.g. emerging needs relative risk ratio 1.65 (99% confidence interval 1.55-1.75) in 2015; established needs relative risk ratio 1.88 (99% confidence interval 1.71-2.06) in 2015). CONCLUSIONS:A large proportion of children starting school each year have SHCN. The types of SHCN that children present with increasingly reflect complex difficulties that require input from both the health and education sectors. Effective responses also need to consider the added impact of disadvantage.