This book series will provide readers with the landscape of mathematics teaching practices in Singapore classroom. In this first book of the series, Theory-Informed Practices, the book will have a collection of teachers' classroom practices that are informed by theory. It will provide classroom exemplars of how teachers make use of theories to inform their practices to better cater to the needs of the learners. This book which targets at the practitioners is written in a way that help the practitioners to be better in consuming and applying such efforts in the own classrooms. It provides the interested readers not only the landscape but also the spectrum of pedagogical approaches and strategies that are theoretically informed and adopted by the Singapore mathematics teachers. This book is written by expert teachers for teachers. It will also be of interest to graduate students, mathematics educators and the international mathematics education community who are looking for greater insights to the Singapore mathematics classrooms.