Students read textbooks about the Nanjing Massacre in a course opened in Nanjing No. 1 Middle School in Nanjing, capital of east China's Jiangsu Province, Dec. 2, 2014. Nanjing opened courses Tuesday for students based on the textbooks "Warning and Thinking", "Memory of Blood and Fire" and "Historical Truth" issued on Monday. In February of this year, China's top legislature designated Dec. 13 as the National Memorial Day to mourn the Nanjing Massacre victims and all of those killed by Japanese invaders. (Xinhua/Sun Can)