In 2000, the National Reading Panel (NRP) identified scientifically based reading instructional practices in the five key areas of phonemic awareness, phonics, fluency vocabulary, and comprehension. The purpose of this study was to determine the strength of the relationship between the degree of implementation of scientifically based reading instruction in K-3 and Grade 3 Pennsylvania System of School Assessment (PSSA) Reading achievement in school districts in Northeastern Pennsylvania (NEPA). Research indicates that throughout the past decade, these same instructional practices were found to be effective. As educators in K-3 worked to prepare students for high-stakes testing in reading, the degree of implementation of these instructional practices were being examined. In this quantitative study, 132 K-3 classroom teachers in 20 schools completed the Revised Teacher's Implementation of Scientifically Based Reading Instruction (TISBRI) survey to determine the school-wide level of implementation of scientifically based reading instruction. Teacher experience within each school was also studied. The results of the survey were compared to the 2012 Grade 3 PSSA Reading mean scale score for each school. Inferential statistics determined that no correlation existed between the level of implementation of scientifically based reading strategies and Grade 3 PSSA Reading achievement. There was a correlation between years of teaching experience and level of implementation of scientifically based reading strategies. The study also concluded that scientifically based fluency instruction correlated to scientifically based reading instruction in phonemic awareness, phonics, vocabulary, and comprehension. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]