Classroom Innovations through Lesson Study is an APEC EDNET (Asia-Pacific Economic Cooperation Education Network) project that aims to improve the quality of education in the area of mathematics. This book includes challenges of lesson study in the world, for example, in Japan and Singapore. Lesson study is one of the best ways to improve the quality of teaching. It is the model approach for improvement of teacher education in the world, and mathematics is the most appropriate subject for sharing the results of lesson study. This book focuses on teacher education and mathematics education, and on curriculum implementation and reforms.