A multimedia-based learning system to teach children with intellectual disabilities (ID) the basic living and science concepts is proposed. The tutorials' development is pedagogically based on Mayer's Cognitive Theory of Multimedia Learning combined with Skinner's Operant Conditioning Model. Two types of tutorials are proposed. In the first type; the contents are developed in a static manner while in the second type; the contents are developed using a domain-specific ontology with text processing tools and Google search engine. Both types of tutorials have shown a considerable improvement in the learning process and allowed the children with ID to improve their cognitive skills and become more proactive in the classroom.