The memories of schoolyard bullying are still fresh for 21-year-old Zhao Shu Ming, whose Japanese grandmother was left behind in China in the closing days of World War II.

After moving to Tokyo, he was admitted to the second grade at age 8. Soon afterward, he quarreled with six classmates and ended up being held down and beaten in the face. Another day, a boy passing out watermelon slices at lunch deliberately dropped one on the floor and told him, "This is yours," as he put it on his tray.

"I could not understand anything that I was told. My main memory is that I deeply regretted not being unable to talk back," Zhao said recently.