Four dissimilar schools each respond to a learning challenge by questioning set-in-stone thinking and taking risks. A K-8 school in Toronto bypasses the traditional--and problematic--long summer vacation to follow a balanced calendar model. Students attend school year-round with two-week breaks scattered throughout the year; both remedial and enrichment classes are offered during the breaks. A Maine high school opens its process for change to parents, students, and faculty--and winds up with a new structure that gives all stakeholders more voice in school decisions. Faculty from South Heights Elementary School tell how the school went from being the lowest to one of the highest performing in their Kentucky school district by adopting a multi-age instructional model. And when a large, outwardly successful high school discovers a significant minority of its youth still falling through the cracks, it adopts many techniques of "small schools" without losing its overall identity.