Students entering high school often bring misconceptions about the nature of science and experimentation with them from middle school. Many also bring a belief that they are not a "science kid" and, therefore, cannot be a strong student in Biology. This belief can lead to a lack of self-efficacy and of student agency in the classroom. Exposure to authentic research experiences has been shown to increase in self-efficacy and scientific reasoning. Typical research experiences have been limited to summers, specialized after school programs and, in many cases, honors students. To circumvent the unequitable access to these experiences and to determine if exposure to authentic research could increase academic and Biology self-efficacy, student agency, and scientific reasoning, a cognitive apprenticeship classroom (CAC) was developed and tested. Students are positioned as apprentice scientists working in a classroom laboratory. The CAC is based on situated cognition (Brown et al., 1989) and on Collins et al.'s (1991) cognitive apprenticeship. Qualitative data were from standardized test scores, the Formal Reasoning Test (Kalinowski & Willoughby, 2019), the Self-efficacy in Biology questionnaire (Baldwin et al., 1999), and the Academic Self-efficacy questionnaire (Pastorelli et al., 2001). Qualitative data included student work samples and reflection questions included in each unit. Students in the CAC showed a significant increase in Biology Self-efficacy (p=0.001) but a decrease in academic self-efficacy (p=0.047). Non-honors students showed a significant increase in scientific reasoning (p=0.035) while honors students' scores remained the same. Qualitative data showed an increase in the depth of student responses from Fall to Spring semester. Taken together, the data indicate that a CAC can increase Biology self-efficacy and, for at least some students, increase scientific reasoning. [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.]