The present dissertation in practice (DiP) proposal delineates an action research study designed to evaluate the use of problem-based learning (PBL) in an eighth-grade earth science class to assess the impact of PBL on student achievement. I have observed that students often struggle with developing an understanding of how the motions of the sun, earth, and moon (SEM) cause observed phenomenon on the earth. In addition, I have observed the unintentional marginalization of cisgender female students within the science classroom. The identification of the problem of practice (PoP) led to the development of the following two research questions: "What are the perceptions of the teacher-researcher while conducting a series of PBL scenarios with eighth-grade students in an earth science class?" "What is the relationship between implementation of PBL by the teacher-researcher on the creation of a more equitable eighth-grade earth science classroom while fostering conceptual change for all students?" The study used an action-research methodology and followed the four-step cycle of "planning," "acting," "developing," and "reflecting." During the planning phase, I developed a problem of practice, conducted a literature review, and developed a research plan. The acting phase involved the collection and analysis of data. The developing phase involved the implementation of an action plan using the collected data. The reflecting phase involved a systematic reflection of the study and the communication of results. The findings of the study show that PBL was somewhat effective in bringing conceptual change in this study. In addition, the actions of the PBL tutor can create a more equitable science classroom, PBL may reduce confusion in science class, and risk-taking is an important aspect of the PBL process. [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.]