There is widespread recognition in educational literatures that academic discourse is important for supporting students' developing understanding in the disciplines of science and mathematics. College and career-ready standards also call for attention to supporting students' learning of how to think and communicate like disciplinary experts. The teaching practice of orchestrating classroom discussion is intended to support students in obtaining higher levels of academic achievement but also to support students' participation in a democratic society. However, research has found that teachers--particularly novice teachers--struggle to orchestrate discussion effectively for science and mathematics. The investigators of this project hypothesize that opportunities to 1) practice orchestrating discussions in simulated classroom environments; 2) receive constructive feedback on their practice; and 3) reflect on that feedback and their experiences with peers and teacher educators, develops preservice teachers' abilities to lead productive classroom discussion. This may allow them to be more effective at orchestrating discussion when they begin teaching real students in science and mathematics classrooms. The project team, which includes investigators from Educational Testing Service (ETS) and software engineers at Mursion, will develop, pilot, and validate eight discussion-oriented performance tasks that will be embedded in an online simulated classroom environment. The resulting research and development products could be used nationwide in teacher preparation and professional development settings to assess and develop teachers' ability to support classroom discussion in science and mathematics.<br/><br/>The Discovery Research K-12 (DRK-12) program seeks to significantly enhance the learning and teaching of science, technology, engineering and mathematics (STEM) by preK-12 students and teachers, through research and development of innovative resources, models, and tools. Projects in the DRK-12 program build on fundamental research in STEM education and prior research and development efforts that provide theoretical and empirical justification for proposed projects. This Early Stage Design and Development project will 1) iteratively develop, pilot, and refine eight science and mathematics discussion-oriented performance tasks (six formative, two summative), scoring rubrics, and rater training materials; 2) deploy the intervention in four university sites, collecting data from 240 prospective teachers in both treatment and business-as-usual courses; and 3) use data analyses and expert review to build a five-part argument for the validity of the assessment and scoring rubrics. Data sources include prospective teachers' background and demographic information, cognitive interviews, surveys, scores on content knowledge for teaching (CKT) instruments, performance and scores on the developed performance tasks, discussion scores on Danielson's Framework for Teaching observation protocol, and case study interviews with prospective teachers. The project team will also conduct interviews with teacher educators and observe classroom debrief sessions with prospective teachers and their teacher educators. The research will examine each teacher's scores on two summative performance tasks administered pre- and post-intervention and will look for evidence of growth across three formative tasks. Linear regression models will be used to understand relationships among teachers' CKT scores, pre-intervention performance task scores, group assignment, and post-intervention performance task scores. A grounded theory approach to coding qualitative data of 24 case study teachers, observations of debrief sessions, and interviews with teacher educators will generate descriptive use cases, illustrating how the tools can support prospective teachers in learning how to facilitate discussions focused on science and mathematics argumentation. Mursion will develop a webpage on its website dedicated to this project that will allow the team to post the new performance-based tasks, scoring rubrics, and examples of performance in the simulated environment for teacher educators, educational researchers, and policy makers and collect feedback from them that can be used as another information source for refining tools and their use. Research findings will also be disseminated by more traditional means, such as papers in peer-reviewed research and practitioner journals and conference presentations.