Determining the effectiveness of many special education interventions is most difficult because of the practical and ethical limitations associated with assigning participants to a control or non-treated group. Using Longitudinal Study of Australian Children data, this article utilised eight different propensity score analysis methods to determine if a cohort of young primary school children receiving special education services significantly improved their literacy and numeracy skills, social skills and their behaviour, two years after the commencement of the special service, in comparison to a ‘matched’ group of students who did not receive special education support. The children receiving special education support performed statistically significantly less well than the different matched groups across all outcome measures. This result is consistent with the findings from two similar studies in the US and calls into question the effectiveness of special education services for the majority of Australian students with additional needs.