The authors examine classroom experiments that treat education as natural development, showing how teachers apply progressive theories in practice. They discuss factors shaping growth, reorganizing curriculum around learners’ interests, the educative role of play, and fostering freedom and individuality. They describe connections between school and community, conceive schools as social settlements, and advocate integrating industry and practical work into instruction to train thinking, habits, and civic responsibility. Case studies of experimental classrooms illustrate methods, classroom organization, and challenges of reform. The overall focus is on making educational theory concrete, aligning school life with children's development, and preparing democratic citizens through active, socially embedded learning.