This book is a guide to collaborative analysis of student learning (CASL). Developed and refined with more than 1200 elementary and secondary teachers, this system combines the best of action research, study groups, standards-based learning, student assessment, teacher reflection, and portfolio assessment. This system of professional inquiry helps identify the teaching methods that are working successfully. The chapters are: (1) "The Benefits of Collaborative Analysis of Student Learning"; (2) "Why CASL Works: The Framework for Teachers' Reflective Inquiry"; (3) "Culture Building: Norms and Skills for Collaborative Inquiry"; (4) "Phases I and II: The Target Learning Area, Initial Assessment, and Focus Students"; (5) "Phases III, IV, and V: Study Group Analysis of Student Work, Finding More Information, Final Assessment, and Reflection"; (6) "Facilitating CASL"; and (7) "Learning for CASL." Appendixes contain session guides for facilitators and directions for CASL portfolios. (Contains 23 figures and 94 references.) (SLD)