Mathematical sciences (12). This project is developing a sequence of virtual field experiences to provide pre-service undergraduate students with early exposure to working directly with K-12 learners. The sequence consists of three three-week modules focusing on a key professional practice: mathematical problem solving, diagnosing student mathematical thinking, and scaffolding mathematical understanding. The modules are customizable in terms of content from algebra, geometry, and probability and statistics; and they build on the unique resources of the Math Forum's Problems of the Week (PoW) environment. This web-based system presents students with challenging nonroutine problems to which written solutions are submitted and for which mentoring is available to deepen students' mathematical understanding. Implementation is taking place at five teacher education programs with diverse student populations, allowing refinement of materials to meet the strengths and needs of a broad representation of pre-service teachers. Project evaluation is providing ongoing data to both project staff and participating instructors concerning: i) the nature of participants' engagement in and use of module activities; ii) the factors influencing the extent and quality of the implementations, and iii) the impact on preservice teachers' mathematical thinking and disposition towards exploring and cultivating mathematical habits of mind in themselves and the K-12 students. The intellectual merit of this project lies in its grounding in the well regarded resources and associated community of the Math Forum and its leveraging of the research findings about online communities of practice resulting from an ongoing investigation, the Online Mentoring Project. In addition the project is informed by findings from an extensive literature on i) the value of early teaching experiences within pre-service teacher education programs and ii) the importance of developing pedagogical content knowledge in teachers along with core content knowledge. Broader impacts are being felt through the diverse set of participating teacher education programs as well as the large community of Math Forum participants.
