Turning Points helps middle schools create challenging, caring, and equitable learning communities that meet the needs of young adolescents as they reach the "turning point" between childhood and adulthood. Based on more than a decade of research and experience, this comprehensive school reform model focuses on improving student learning through teacher collaboration and data-based inquiry. Turning Points provides member schools with intensive on-site coaching and professional development. The Turning Points design recognizes that schools must provide the building blocks for adolescent development and preparation for life. Turning Points schools focus on developing students' intellectual capacities while providing opportunities for experiences that meet their emotional and interpersonal needs. This guide provides a framework for thinking about classroom assessment in the middle grades, and a set of strategies for action. Like the other Turning Points guides, it aims to distill the best thinking and research on a critical facet of the design, offer useful tools, and point the way to other resources. Appendices include: (1) Julie Craven's Women's History Oratory Project Rubric and Checklist; (2) Portfolio Reflection Examples; (3) 6+1 Trait[TM] Writing Rubric and List of Useful Websites; (4) Mission Hill School's Graduation Requirements and Portfolio Review Process; and (5) The Vertical Slice Protocol: Sampling Student Work.