Roland, a ed tech scholar from Canada, visited our Institute in this week and we had a short sharing with him. He is a fully student-centered scholar and very keen on talking about the nature of knowledge. He adapted a full framework from Carl Bereiter as there are three knowledge of world. World one is the physical world and we can learn from experience. World two is the conceptual world that we learned from schools and books. World three is the artifacts that we built from interaction with W1 and W2. Under this framework, our teaching and learning should be shifted from teacher-centerd focusing on W1 and W2 to student-centered on W3 faciliating students to create their own knowledge by constructing artifacts. How can the teachers in HK can adapt such framwork? Roladn said he faces the same problem in Canada as in HK, but it is his belief.