This essay describes charter school development and the 3-year Philadelphia (Pennsylvania) Schools Collaborative, which worked with educators and parents to transform comprehensive high schools, increase student outcomes, and establish teacher engagement and parental involvement. Charter schools (intellectual and emotional communities of adults, students, teachers, parents, counselors, and university faculty that nurture an engaging educational experience across 4 years and enjoy ongoing relationships inside urban public high schools) were designed. Neighborhood high schools and the Central District were radically reformed via communication and decision making governance, school organization, professional development, student and family supports, assessment/evaluation, and partnerships/focus on transitions. Eight million dollars and 3 years later, the first phase of the Collaborative shows that school-based restructuring (a relentlessly supported strategic agenda focusing on transformed governance, instruction, structure, assessment, and student supports) improves student outcomes even in poverty-ridden districts; external investment enhances student outcomes, especially monies instigating systemic change; participatory and strategically guided decision making lead to improved student outcomes; schools most "at risk" are most susceptible to early improvements, especially with high external and deep school-based investment; and educationally rich and intimate learning communities enhance student learning, teacher collaboration, and parent involvement. (Contains 20 references.) (RLC)