Project Based Learning (PBL) is an instructional strategy used to aid in the improvement of student achievement by incorporating a project as the medium to collaborate and augment competency and skills. The purpose of this study was to explore and examine the implementation of PBL via the use of a district-wide PBL instructional curriculum for high school chemistry. The implementation of the district-wide PBL instructional curriculum for high school chemistry was shown to increase student engagement, student collaboration, as well as upsurge student interest in the subject of chemistry. In addition, instructors that implemented PBL, as described in the district-wide PBL instructional curriculum for high school chemistry, used various techniques and strategies for instruction, scaffolding lessons for various learning environments, and provided students with prerequisite concepts that might be lacking. The research was conducted on eight certified, high school chemistry teachers that utilized PBL in a South Atlantic school district via the district-wide PBL based instructional curriculum for high school chemistry for at least one year. The findings of the data analysis add to literature regarding the educational enterprise and close the gap regarding educators' responses and perspectives about the positive, negative, and overall aspects of PBL implementation via a district-wide curriculum. In this study, implementation of PBL as described in the PBL-based instructional curriculum for high school chemistry was found to impact student achievement, student engagement, and heavily influence teacher instruction practices. [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.]