Students with a disability in inclusive classes often face problems with peer acceptance, friendships and peer interactions. In this paper, the relationship between these difficulties in social participation and the attitudes that typically developing adolescents hold towards peers with a disability at the level of the class was explored. A cross-sectional study was performed involving 1866 typically developing peers, 86 children with autism spectrum disorder (ASD) and 61 children with sensory and/or motor limitations (FYS) in their first year of secondary education. Results showed that students with ASD as well as students with FYS were less accepted by peers, had fewer reciprocal friendships and were less engaged in peer interactions than their typically developing peers. The attitudes of typically developing adolescents towards their peers with a disability at the level of the class were neutral. The relationship between class attitudes and peer acceptance, friendships and peer interactions of students with ASD and FYS was moderated by type of disability. For adolescents with FYS, a significant positive relationship was found; for adolescents with ASD, no significant relationship was detected.