This collection of four case studies discusses the work of teachers and their efforts to change their classrooms, schools, and districts. The case studies show that teachers can learn to use their own strengths and talents, knowledge, shared vision, and commitment to student growth and development to effect change. The first case study, "Santa Ynez Valley Union High School" (Jon Snyder), documents how a rural California high school brought together internal and external resources and expertise to create a model for school change, and reports the difficulty and complexity of mobilizing "whole school" change and of sustaining optimism and momentum in face of early setbacks. "Pod 200 Clubs: A Multicultural Curriculum in Action--the Walt Disney Magnet School" (Lynette Hill with the assistance of Alice Weaver) describes creation of a multicultural and integrated curriculum within an open-classroom team-teaching environment in Chicago (Illinois) through student participation in interest groups. "Lompoc Valley Middle School Challenger Program" (Marianne D'Emidio-Caston and Jon Snyder) discusses creation of a California school-within-a-school which focuses on active learning, accountability, community of learners, integrated curriculum, and changing relationships among teachers and between teachers and parents. "The Foundations School: The School of Choice" (Lynette Hill with the assistance of Alice Weaver) was brought about by Chicago (Illinois) teachers who saw their role as facilitators in the learning process and who believed in whole language, child-centered classrooms and an interdisciplinary approach to learning. Some generalizations are woven throughout the fabric of the case studies that offer insights about networks as supports for intellectual and social change, about the subtleties and nuances of individual and collective learning when they are part of the change process in schools, and about the tensions that arise as teachers bring knowledge from the outside to change the inside of their schools. (JDD)