This study investigates in-service early childhood teachers' "practical knowledge" (Elbaz, 1981) in implementing changes in the classroom in the Republic of Singapore. In Singapore, many early childhood classrooms are teacher-directed where learning takes place in large groups. As part of the in-service teacher education program, a learner-centered practicum required teachers to visualize how they can include children's choice through designing learning corners and implementing small group learning. This investigation unveils how teachers used their "practical knowledge" to implement change and documents evidences of the change after 3 to 5 years of its initial implementation. It also highlights conditions for change and offers suggestions to policy makers, curriculum designers, and teacher educators in educating for change.