Project-Based Learning (PBL) is a teaching method in which students learn by actively engaging in real-world, personally meaningful projects that allow conceptual transformation to occur within the educational process while fostering intellectual curiosity in a supportive learning environment. PBL supports students developing deep content knowledge, critical thinking, collaboration, and communication skills. (PBLworks, 2021). What effect, if any, does PBL instruction have on academic achievement? Insight into PBL impacts on student achievement may inform teachers, administrators, and other stakeholders about the critical components of PBL and the relationship between those components and student academic achievement (Goo, 2020). This study aimed to align PBL instructional methods to 4th grade National Assessment of Educational Progress (NAEP) data to determine the effectiveness of PBL on student academic achievement in reading, mathematics, and science content areas. This quantitative study includes an analysis of 4th grade content area data from the NAEP database in relation to the study's guiding philosophies and theories supporting PBL instructional practices. Strategies used to analyze the data focused on sub-questions within the NAEP data set to answer the larger research question regarding PBL and its impact on student academic achievement. The evidence is displayed through crosstabulation charts, in the appendix, allowing the reader to analyze results and shows several key findings that relate PBL instruction to student academic achievement in reading, mathematics, and science across 4th grade students. The results of this study may help leaders improve the implementation of scripted versus semi-scripted curriculum decisions in schools and the amount of autonomy teachers can have with assigned curriculum choices. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]