Previous research is not conclusive in detailing the prevalence of challenging behaviour and its correlates in children with intellectual disabilities in school settings in particular. In the current study, an amended version of the Behaviour Problems Inventory -- Short Form was used to collect data from a sample of 321 students in a special school. Prevalence of challenging behaviour was high with 53% of students having at least one challenging behaviour, 36.4% self-injurious behaviour, 30.2% aggressive/destructive behaviour, and 25.9% stereotyped behaviour. Challenging behaviour overall was significantly associated with poorer adaptive behaviour skills and the presence of an autism diagnosis. Stereotyped behaviour was also significantly associated with higher levels of neighbourhood deprivation and age. The implications of these findings for schools and future research are discussed.