Hong Kong students are preparing for a showdown with Beijing over democratic reforms by boycotting classes on Monday as a restive younger generation challenges the Chinese Communist Party's tightening grip on the city.

The former British colony returned to China in 1997 with a high degree of autonomy, but Beijing's rejection of the right to freely choose the city's next leader has prompted threats from activists to shut down the Central financial district as part of their prodemocracy campaign.

As a prelude to the "Occupy Central" shutdown expected next month, students from 24 universities and colleges plan a weeklong citywide campaign of civil disobedience, including classroom strikes, mass gatherings and downtown protests.