Many children with intellectual disability, including children with Down syndrome, have teachers who are unsure what type of reading instruction is likely to increase outcomes for their students. Effectiveness of two commercially available, evidence-based reading interventions was evaluated through 3 multiple baseline across participants, single-subject research design studies involving 15 children with Down syndrome between the ages of 5 and 13 years. School staff implemented the phonological awareness and decoding interventions for an average of 25 sessions across approximately 12 weeks. Results indicate improvements in the reading of taught phonetically regular and high frequency words associated with the decoding intervention, but no generalization to oral reading fluency. No reliable gains were associated with the phonological awareness intervention. Implications for research and practice are discussed. (Contains 3 tables and 3 figures.)