Lesson Study has a long history in Japan as an in-service teacher professional development approach (Watanabe, 2002) which involves teachers working together in iterative cycles of planning, teaching and assessing lessons in their school. In the past two decades, the approach has attracted the interest of researchers, as it is believed to be a key factor in the development of pedagogical knowledge and competence in Japanese teachers as well as in the superiority of Japanese students in international test scores as reported by the Third International Mathematics and Science Study (TIMSS) video study in 1999 (Stigler & Hiebert, 1999). A steady growth of Lesson Study in places such as the United States, Hong Kong, Singapore, Brunei, Malaysia, Indonesia, Sweden, Australia and the UK, etc. has been witnessed in recent years, and research has indicated that the approach seems to be able to present a viable framework for improved instruction, which can contribute to improved student learning (Cheung & Wong, 2014; Ko, 2014; Lewis, Perry, & Murata, 2006; Xu & Pedder, 2015). The Lesson Study approach has further been developed into an enriched version known as Learning Study by Hong Kong researchers (Lo, Pong, & Chik 2005). Learning Study is similar to Lesson Study in some aspects, as both are a type of collaborative action research that involves teachers and university researchers working together over a period of time on improving the research lesson(s). However, in terms of goals, Lesson Study emphasizes facilitating teachers’ professional development and school improvement (Sato, 2004), whereas Learning Study differs in that it is theory driven, with Variation Theory (Marton and Booth 1997) being used as an explicit theoretical framework to guide, analyze and evaluate the pedagogical approach (Ko, 2014).