Lesson Study is a very simple idea. If you want to improve classroom instruction, the change has to be teacher-driven and student-focused. Lesson Study model has been found to be one of the key component for the impressive mathematical performance of the Japanese students in international mathematics achievement studies. Lesson Study has gained the acceptance as an effective model for Professional development and instructional improvement. It spread rapidly in United States of America since 1999.
Lesson Study was introduced to Sri Lanka in 2006, by Professor Rajee Amarasinghe from California State University, Fresno through a six-month long project conducted by the Department of Mathematics, University of Colombo. Dr. Kirthi Premadasa from The Department of Mathematics coordinated this multi Phase project with the support from mathematics department faculty. Mr. W.M. Pragnadarshana from faculty of education collected research data on teacher change. Thirty six teachers from around the country participated in the project. Both teachers and students alike embraced the concept of lesson study heartily. The academic staff of the Department of Mathematics, lead by the Head, Mr. Chanakya Wijerathne provided total support with resources and infrastructure.