Although inclusion generally affects students with special educational needs positively, it remains unclear whether specific integrative school measures have beneficial or detrimental effects on their academic performance and perceived inclusion. Unlike previous studies, the present paper differentiates between various types of integrative school measures, such as curriculum modifications (i.e. reduced individual learning objectives; RILO) and accommodations (AC). It explores their effects on academic performance and perceived inclusion. Analyses are based on a prospective longitudinal study of 1123 students (baseline at fifth/sixth grade, mean age 12.4 years old, and follow-up at eighth/ninth grade, mean age 15.3). Propensity-score-matching based on potential confounders was used to estimate relative changes in similar students' academic performance and perceived inclusion, with and without RILO or AC. RILO had significant negative effects on maths and overall academic performance. AC, however, had significant positive effects on academic performance and no negative side effects on perceived inclusion. School teachers and educational professionals should consider the opportunities and risks of different integrative school measures and use RILO in an inclusive, non-stigmatising manner.