HONG KONG — Thousands of Hong Kong university students abandoned classes on Monday to rally against Chinese government limits on voting rights, a bellwether demonstration of the city’s appetite for turning smoldering discontent into street-level opposition.

“University students must shoulder the responsibility of these times,” Nathan Law Kwun-chung, the acting president of the student union of Lingnan University, told the crowd crammed into the main quad at the Chinese University of Hong Kong. Some held banners of their universities, and many others umbrellas to ward off the sun in this tropical former British colony.

“Boycotting classes is just the first wave of resistance,” Mr. Law said. “Today is not the last step for us all. It’s the first step, and countless resistance campaigns will bear fruit.”

The striking students, who have said they will boycott classes for the week, are at the vanguard of a planned succession of protests against rules proposed by China that would effectively give Beijing the right to screen candidates for the post of Hong Kong’s top official.