Despite decades of research, NOS is still rarely explicitly and accurately taught in K-12 schools (Abd-El-Khalick & Lederman, 2023). Teachers often address NOS ineffectively as a result of inadequate knowledge of NOS and science content (Wahbeh & Abd-El-Khalick, 2014) as well as NOS pedagogy (Hanuscin et al., 2011). A variety of contextual factors (e.g., school administration, student characteristics, teacher emotions) also make NOS teaching more challenging (Akerson et al., 2014). Yet, a focus on challenges to NOS teaching misses the broader picture of what it is like to teach NOS in K-12. Teachers' practices are guided by a number of sometimes contradictory aims, so teachers often make decisions not aligned to their values (Berry, 2007). Consequently, a teacher's practice can be described in terms of the tensions they navigate. Teacher educators need a strong understanding of the experience of teaching NOS in K-12 classrooms in order to better prepare and support preservice and inservice teachers for teaching NOS. Self-studies are one means of sharing experiential knowledge of practice among teacher educators (LaBoskey, 2004). To this end, this self-study describes (1) tensions experienced by a non-traditional teacher educator teaching NOS to middle school students during a semester-long experience, and (2) amplifiers, filters, and professional knowledge bases that influenced how NOS-related tensions were navigated. Implications and recommendations for teacher education are discussed in light of the results of this self-study. [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.]