Detailed accounts of teaching can shed light on the nature and prevalence of active learning, yet common approaches reduce teaching to unidimensional descriptors or binary categorizations. In this paper, I use the instructional systems-of-practice framework and the Teaching Dimensions Observation Protocol (TDOP) to advance an approach to thinking about teaching in science classrooms in more multidimensional terms. Using descriptive statistics and social network analysis, I examine the teaching practices employed by a group of science and engineering faculty (n = 56). Results indicate the extensive use of lecturing with premade visuals (observed in 65% of all 2-minute intervals comprising a class). However, the majority of instructors (n = 34) lectured for periods of 20 minutes or less. Using the Differentiated Overt Learning Activities (Chi & Wylie, 2014) framework to interpret TDOP codes, the data reveal lower rates of active learning modalities including "being active" (students answering questions, 28%; students problem solving (PS),15%), "being constructive" (students asking questions, 4%; students doing creative tasks, 2%), and "being interactive" (students working with peers to do creative tasks, 2%). Results indicate variation across disciplines and course contexts, that active learning is embedded within PowerPoint lectures, and that small group work exercises are not synonymous with constructivist activities. Implications for research, practice, and policy are discussed.