It was always going to be a challenge. But then, when you've reached the grand finals of Division Two of the 12th Nesta-SCMP Debating Competition, the speakers know it's not going to be easy.
The subject was science and the issue on the table was the pros and cons of fuel-cell technology in cars - when electricity is generated from chemical reactions in a kind of everlasting battery. Tricky.
SKH Chan Young Secondary School went head to head against True Light Middle School of Hong Kong at the Science Museum in Tsim Sha Tsui.
Both schools had seen off more than a dozen other teams so no one expected a walkover with the motion: "We should adopt fuel cell technology to provide solutions to exhaust-gas problems from cars."
Chan Young was arguing for the motion, claiming fuel-cell technology offered an efficient way to cut air pollution. True Light took the opposite stance, claiming the new technology did not live up to its environmentally-friendly image.
The line-up of judges was: David Walker, English teacher from Hoi Ping Chamber of Commerce Secondary School; Jeff Bell, English teacher from HKFEW Wong Cho Bau Secondary School; and Lesley Yellowlees, head of the College of Science and Engineering at the University of Edinburgh, Scotland.
Vanessa Co, a Form Five student from True Light, said huge amounts of carbon dioxide were produced to extract the hydrogen needed to generate electricity in a fuel cell. This did not make it a green fuel solution at all.
Her Form Four teammate, Emma Chan, added: "Fuel cells are impractical. It is more of a technological illusion than a breakthrough. There will not be enough money to make it work."
Chan Young countered that their opponents just cared about money. Form Two student Tiffany Pang Chung-yau said: "Fuel-cell cars are the ultimate eco-friendly cars. With air pollution, financial losses from people getting ill or dying would be more costly than the money spent on fuel cells."
For the judges, it was a tough call, too. In the end, they decided Chan Young had the edge and named them the champions. However, True Light's Vanessa was named best speaker.
Yellowlees praised both teams for their thorough research. "The speakers have shown that they have put in a lot of work practising their speeches and working on research," she said.
The contest is organised by the Native English Speaking Teachers' Association and the South China Morning Post.