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This randomised controlled trial used a mixed-methods approach to investigate the frequency and how elementary teachers integrated engineering design (ED) principles into their science instruction following professional development (PD). The ED components of the PD were aligned with Cunningham and Carlsen's [(2014). Teaching engineering practices. Journal of Science Teacher Education, 25, 197-210] guidelines for ED PD and promoted inclusion of ED within science teaching. The treatment group included 219 teachers from 83 schools. Participants in the control group included 145 teachers from 60 schools in a mid-Atlantic state. Data sources, including lesson overviews and videotaped classroom observations, were analysed quantitatively to determine the frequency of ED integration and qualitatively to describe how teachers incorporated ED into instruction after attending the PD. Results indicated more participants who attended the PD (55%) incorporated ED into instruction compared with the control participants (24%), χ 2 (1, n = 401) = 33.225, p < .001, r f = 0.308. Treatment and control teachers taught similar science content (p's > .05) through ED lessons. In ED lessons, students typically conducted research and created and tested initial designs. The results suggest the PD supported teachers in implementing ED into their science instruction and support the efficacy of using Cunningham and Carlsen's (2014) guidelines to inform ED PD design.

Recent education reforms including the Next GenerationScience Standards emphasize integrating engineering into K-12 science instruction. Although prior studies have characterized engineering design (ED) in K-12 settings, no validated protocols attempt to characterize ED integration in secondary science classrooms. The present study used the ED and observation protocol literature to develop, validate, and test the reliability of the Classroom Observation Protocol for Engineering Design (COPED) instrument. Consistent with the ED literature, the COPED characterizes two components of ED: process and habits of mind. To use COPED, researchers code for ED process components, engineering habits of mind, and instructional grouping in 2-min increments. Researchers also record qualitative field notes. Post-observation, researchers include descriptions of disciplin-

Problem‐based learning (PBL) and science, technology, engineering, and mathematics (STEM) are two acronyms widely visible in education literature today. However, few studies have explored these in connection with one another, specifically with regard to teacher preparation. This study investigated how 47 prospective elementary teachers developed PBL units and how they integrated STEM and other disciplines into those units. It also addressed the affordances and constraints of integrated STEM as perceived by the prospective elementary teachers. Data sources in this multimethod study included PBL units and interviews. Findings revealed that all of the units integrated at least two of the STEM disciplines, as well as literacy, in a variety of ways. The prospective teachers articulated perceived benefits of integrated STEM, such as: making connections across content areas, preparing students for the real world, teaching students that failure is not a bad thing, and providing future opportunities. They also addressed perceived barriers of integrated STEM, such as: having limited experience with the content, diminishing the effect of individual content areas, and needing better curriculum alignment. Overall, this study provides evidence that PBL can be a pedagogical approach to integrate STEM. Implications for teachers, teacher educators, and curriculum specialists are discussed.

Science teaching anxiety is negative emotion that inhibits a teacher's ability to start, proceed, or finish a science teaching task. Despite its detrimental effects on teachers' science teaching quality and practices, there is limited research on science teaching anxiety. To advance research in this area, there is a need for a psychometrically sound instrument assessing teachers' science teaching anxiety. This study presents the development and psychometric properties of the Science Teaching Anxiety Scale (STAS) in preservice elementary teachers (N = 191) using a Rasch analysis. In addition, it examines the relationships among science teaching anxiety, science interest, and science teaching efficacy (self‐efficacy and outcome expectancy). Results indicated that the STAS has promising validity and reliability for use in future research. Moreover, science teaching anxiety and science interest were significant predictors of teaching self‐efficacy in preservice elementary teachers. Implications for researchers, teacher educators, and individuals who work with new teachers are discussed.