Over the past three decades, many countries in the world have displayed increasing racial, ethnic, linguistic, and cultural diversities. No matter where you go -- be it Singapore, New Zealand, Canada, Austria, South Africa, China or England, for sure you would see and hear it. We face the challenges of educating the diverse student populations, equal distribution of education resources, and the problems of achievement gaps between mainstream students and students from racial and ethnic groups.  As this has become a global phenomenon, a conversation at the global level on how these challenges manifest in different countries, or grappled by different education systems under different social contexts will be very meaningful.  Hope you would share your stories here with everyone. <--break--> To me, achievement gap refers to the disparity on academic performance between advantaged and disadvantaged groups of students. In the United States, the gap in academic achievement persists between minority and disadvantaged students and their White counterparts. White students tend to outperform students of color, and wealthier students often do better than poorer ones.  The 2007 Nation’s Report Card shows that achievement gap is still real and deep in US schools. For example, the average score gap between White and Black eighth-graders on the national Mathematics Report Card is more than 30 points and that between White and Hispanic students is about 25 points. What are the roots of the gaps? What should we do about it?