Thanks to Hong Kong's Leisure and Cultural Services Department and the Chinese General Chamber of Commerce, the local students went on a seven-day trip to Beijing. They visited the Astronaut Training Centre and the Jiuquan Satellite Launch Centre.
Most were girls, buoyed by the success of Liu Yang, who became the mainland's first female astronaut in space in June.
"Liu shows how women hold up half the sky," says Ko Ka-yan, a Form Four student at STFA Lee Shau Kee College. "She aroused my curiosity in the universe."
For two days, the students tested their physical endurance at the astronaut training centre. It has facilities to simulate the weightless environment of space.
Kong Yik-kiu went on a treadmill specially designed for the user to run while being suspended horizontally. The 16-year-old, who studies at Tsuen Wan Public Ho Chuen Yiu Memorial College, says it made her feel as if she was an upside-down turtle.
"My back had no support," she says. "It felt like I was walking on stilts. It was difficult to move."
Fellow participant Wong Ching-yau, who also studies at STFA Lee Shau Kee College, felt dizzy as blood rushed to her head when she spent a minute strapped to a rotating bed that could tilt 45degrees backwards and forwards. This training technique helps strengthen astronauts' heart and blood vessels.
Wong Kwok-wai, of William Booth Secondary School (Salvation Army), marvelled at the stamina of astronauts. "I felt ill after just a fraction of the 15-minute session on a rotating chair that astronauts have to train on regularly," says Kwok-wai. "They live a tough life to achieve their space missions."
Then it was time for lunch - in the astronaut centre's kitchen.
And the food wasn't simply some tasteless space gruel.
"The food was vacuum-packed and ready to eat," says Au Lai-wan, who studies at Pope Paul VI College. She particularly liked the vanilla-flavoured space ice-cream, which looks like sugar cubes and melts in the mouth like marshmallows.
The Hong Kong students then met astronauts Yang Liwei, Nie Haisheng, Fei Junlong and Liu Boming for a session of picture-taking and questions and answers.
Ka-yan asked Yang, the mainland's first man in space, if the Great Wall was visible in space. "He said no," she says. "But he said the planet looked bright and he could recognise major cities."