Nearly three months of youth-dominated protests — calling for democracy and an independent inquiry into police conduct — will be tested as classes resume with the end of the summer break in the semiautonomous Chinese territory.

The young protesters strove to demonstrate their continued determination with Monday’s school boycott, the first of a planned two-day strike.

Jacky So, president of the Chinese University of Hong Kong’s student union, said 30,000 students attended a rally on campus. They dressed in black and wore face masks, waving banners for their student associations and black signs with the Chinese character for “Strike.”

Separately, high school students who were skipping class rallied in Edinburgh Place, a public square in Hong Kong’s central business district. Teenagers spoke to the crowd from a stage with a backdrop that read: “With no future, there’s no need to go to class.”