This document discusses factors that impact student learning and identifies teacher effectiveness as having the greatest impact. It summarizes a study that tracked students over 2 years in different school and teacher environments. The study found that students taught by ineffective teachers for 2 years dropped from the 50th to 3rd percentile, while those with effective teachers rose to the 96th percentile. The document provides research supporting direct instruction models and instructional strategies proven to improve student achievement, such as setting clear learning objectives and checking for understanding. It emphasizes the importance of recruiting and retaining effective teachers to provide students with an exceptional learning environment.