Students with an intellectual disability often struggle with significant language delays or impairments. Although this population of students can acquire language skills, they often require methods of explicit instruction of language skills to do so. Direct Instruction (DI), a system of explicit and systematic instruction, could be one of these methods. The purpose of this study was to investigate the effects of DI on the use of and response to prepositions by three elementary school students with an intellectual disability. A multiple baseline design across prepositions was used in this study with replication across students. The researcher used DI to model examples and nonexamples (i.e., "This is above," "This is not above.") of three prepositions (e.g., above, behind, beneath) to the students. In addition to the instructional sessions, students participated in three generalization activities. Results of this study showed a functional relationship between Direct Instruction and students' use of and response to prepositions. Students demonstrated the ability to use and respond to prepositions consistently after receiving DI on each of the three target prepositions. Furthermore, all three students maintained the skill up to 56 days from instruction on each of the prepositions. These findings are important to this population of students because of the need for explicit and systematic instruction of language skills; it has been demonstrated that DI is an effective instructional tool in teaching these skills in an efficient and effective way.