ARTICLE High School Physics Students’ Personal Epistemologies and School Science Practice Muhammet Mustafa Alpaslan 1 & Bugrahan Yalvac 2 & Cathleen Loving 2 # Springer Science+Business Media B.V. 2017 Abstract This case study explores students’ physics-related personal epistemologies in school science practices. The school science practices of nine eleventh grade students in a physics class were audio-taped over 6 weeks. The students were also interviewed to find out their ideas on the nature of scientific knowledge after each activity. Analysis of transcripts yielded several epistemological resources that students activated in their school science practice. The findings show that there is inconsistency between students’ definitions of scientific theories and their epistemological judgments. Analysis revealed that students used several epistemological resources to decide on the accuracy of their data including accuracy via following the right procedure and accuracy via what the others find. Traditional, formulation-based, physics instruction might have led students to activate naive epistemological resources that prevent them to participate in the practice of science in ways that are more meaningful. Implications for future studies are presented. 1 Introduction Epistemology is the branch of philosophy concerned with the study of knowledge (Kvanvig 2014; Matthews 1993). Two central questions of epistemology refer to the facets of the nature of knowledge and its production: (a) how we know what we know, and (b) why we believe it (Sandoval 2005). Constructing its meaning from epistemology, personal epistemology is defined as what individuals believe about what counts as knowledge, how individuals come to know, and how knowledge is constructed and evaluated (Hofer 2008; Kelly 2016). Personal epistemology influences how students make meaning, solve problems, and learn strategies (Hammer 1994; Hofer 2008; Sandoval 2005). Recent science education documents have Sci & Educ DOI 10.1007/s11191-017-9930-2 * Muhammet Mustafa Alpaslan mustafaalpaslan@mu.edu.tr 1 Department of Mathematics and Science Education, Muğla Sitki Ko man University, Kötekli Mah, 48000 Muğla, Turkey 2 Department of Teaching, Learning, and Culture, Texas A&M University, College Station, TX, USA