Educational reform and accountability are on the rise in American schools; still many students continue to struggle with reading achievement. The purpose of this study was to determine if explicit instruction (EI) of reading comprehension strategies had an impact on student reading achievement. Drawing from the constructivist theory, the EI model provided a clear explanation of the strategy, encouraged student engagement, activated student’s prior knowledge, and provided practice and immediate teacher feedback The research question that was addressed in this study was how EI of scientifically based research reading comprehension strategies effected student reading achievement in terms of standardized test scores of developmental reading level (DRL), reading fluency (RF), and reading comprehension (RC). The single group design included pretest of the 3 reading measures followed by a treatment and a posttest using a convenience sample of 19 third grade students in an elementary school in a suburb of Georgia. The research question was tested through an analysis of DRL, RF and RC scores using paired samples t tests conducted after cross-curricular EI designed to focus on developmental reading level, reading fluency, and reading comprehension ability. Statistically significant increases in scores for all three areas of reading suggested that the intervention may represent a balanced approach to literacy. The treatment program is recommended as a framework for literacy which would be useful for educators in creating new curricula. This study offers implications for positive social change through an enhancement of effective instructional practices and an increase in reading achievement which is at the center of early academic achievement and provides the foundation for learning and achievement throughout life.