The purpose of this article was twofold: (1) to explore the feasibility of the regression discontinuity design (RDD) in response-to-intervention implementation research and (2) to expand upon the limited research on vocabulary instruction for kindergarten students who are at risk for reading failure due to limited vocabularies. This pilot study…

Vocabulary knowledge at school entry is a robust predictor of later reading achievement. Many children begin formal reading instruction at a significant disadvantage due to low levels of vocabulary. Until recently, relatively few research studies examined the efficacy of vocabulary interventions for children in the early primary grades (e.g.,…