This study explored the perceptions of special education teachers of students with intellectual disabilities at three elementary schools in Saudi Arabia regarding the instructional practices and content used for teaching such students mathematics. The research employed a qualitative multiple case study design and used an open-ended questionnaire, artifacts, and teacher interviews with 14 special education teachers. By employing thematic analysis of the data collected, the following major issues were identified: (a) there is a strong focus on teaching only numbers; (b) there is an emphasis on teaching functional life skills rather than academic mathematics skills; and (c) mathematics instruction emphasizes procedural mathematics rather than mathematical understanding, also known as conceptual mathematics. These findings illustrated that elementary school students with ID in the sample did not receive comprehensive mathematics education in terms of either content or instructional practices. It might be beneficial for future studies to replicate and extend this research to incorporate observations of the classroom to obtain objective data on teachers' actual practices while instructing students with ID in mathematics.