The current article examines what factors explained the success of a reading program delivered by older adult volunteers to at-risk early readers. The article also examines the direction of the relationship over time (both direct and mediated) between reading achievement, frequency of reading at home, and academic self-beliefs. Two hundred and twenty nine socially disadvantaged children recruited at the start of first and second grade at risk of reading failure participated in the randomized controlled trial study over an 18-month period. The results from structural equation modeling show the combined instructional and emotional support was a proximal outcome, whose distal outcomes included gains in reading achievement. There was no evidence that either academic self-beliefs or frequency of reading at home mediated program impact on reading achievement. In addition, academic self-beliefs became more accurate and stable as children advanced through school. Reading achievement mediated the impact of earlier reading achievement on both academic self-beliefs and frequency of reading at home for children entering second and third grade. In contrast, for the youngest children (at the start of first grade), academic self-beliefs were negatively associated with subsequent academic self-beliefs and frequency of reading at home.