One angry parent in Beijing complained that her child had to make posters comparing President Bill Clinton to Adolph Hitler, and reproduce swastikas in her classroom.
But Guangzhou secondary teacher Chen Bing said that anger among teachers and secondary students was genuine.
"They've been writing articles denouncing the bombing and making ugly caricatures of Clinton on computers, some making him look like Hitler," she said.
Anti-NATO activities were also organised by school student unions.
"Teachers are asking students to study hard to make China stronger. They know that if China is strong the Americans will not look down on us anymore," said Ms Chen.
There have also been reports that foreign teachers in some smaller cities have been advised to go home because their safety could not be guaranteed.
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