Despite recent research findings that implicate a long list of student variables that predict reading success or failure, these predictor variables have not been considered in the context of contemporary models of multitiered schoolwide reading intervention. This longitudinal, retrospective study follows 668 kindergarten and first-grade students identified as at risk for later reading difficulties through third grade. Key predictor variables were examined to determine their validity for predicting initial status and growth on oral reading fluency, third-grade oral reading fluency, and third-grade performance on a standardized test of reading. Results are provided in light of the instructional model provided. Implications for instruction and assessment are discussed. (Contains 6 tables and 2 figures.)