Testing and certification (T&C) are keys to scientific discovery. To encourage secondary school students to integrate T&C principles into their experiments – and spark a passion for science – the Hong Kong Council for Testing and Certification (HKCTC) has co-organised the annual “Digi-Science” Video Production Competition with the Hong Kong Association for Science and Mathematics Education (HKASME) since 2016.
This year’s theme, “Testing Science – Batteries,” invited students to think beyond textbooks and explore the possibilities of electricity generation through creative experiments using recycled materials. Students embraced the challenge, immersing themselves in months of hands-on science learning.
Each team submitted a two-minute video featuring bold hypotheses and thoughtful testing. By engaging in hands-on experience and their findings in the video, students learned how T&C validates scientific claims and ensures quality and safety. Their work vividly demonstrated the intersection of T&C and everyday life.
The judging panel was composed of five HKCTC members: Dr Cheung Kwai-chung; Dr Gray Ho; Dr Lesly Lam; Robert Lui and Ir Dr Fanny Tang, as well as judges from HKASME. The panel praised the consistently high quality of entries, saying, “Most students showed strong presentation skills and a deeper understanding of testing - a credit to the HKCTC.”
“Many teams used vivid storytelling to explain their ideas and adopted advanced scientific procedures,” Lam added. “They proposed innovative hypotheses, conducted extensive research and referenced scientific literature to select appropriate testing methods. Their meticulous data collection shows just how self-motivated this learning experience was – it went far beyond their curriculum.”
In addition to showcasing impressive experiments, the competition served as a holistic platform for students to unleash their creativity by developing compelling narratives that clearly and succinctly explained the core concepts behind their work.
“The winning teams’ videos demonstrate a flair for using role play to present their experiments in a vivid and engaging manner,” Lam observed.
He also suggested areas for improvement, such as more effective organisation of information and a sharper selection of key messages to include in the videos.
“These are vital skills for students, whether in further studies or in the workplace,” Lam added.
The competition plays a valuable role in helping secondary students appreciate the importance of testing and certification – not only in scientific discovery but also in ensuring product safety and quality.
“Underlying all these ideas is sustainability,” Lam remarked. “We aim to encourage students to be more thoughtful and to develop creative, practical methods to make the most of available resources.”
Senior Secondary Division Champion: St Paul’s Convent School
Title of video: Voltage Voyage at the Kitchen – Powering Up Through Household Materials
Team members: Celina Ho-yee Ching, Ashley Lok-wai Chun, Amanda Shi Chi-yiu
Driven to explore the electrical potential of common household items – such as table salt, caustic soda, bleach and aluminium beverage cans – the team embarked on an enlightening testing journey. “We ran repeated tests to identify the most effective materials and get consistent and accurate readings on voltage and current,” Amanda said.
To build their hypothesis, they studied scientific papers, tested numerous combinations and used multimeters to measure outputs. Their final set-up successfully powered an LED bulb for 1.5 hours. “Altogether, we tested eight material combinations and matched each with the right-sized cans to optimise the electrolyte,” Amanda added.
One of the biggest challenges was the aluminium oxide coating on the cans, which required an average two-hour reaction time per experiment. “We were so eager to see the results each time – cheering on our experiments like a sports team,” Ashley recalled with a smile.
For Amanda, the real reward was applying textbook knowledge to solve everyday problems. The team’s winning video used storytelling and visual hints to guide the narrative. “We were actually inspired by a question on our test paper,” Ashley said.
“We thoroughly enjoyed the whole experience, from penning the script to acting in front of the camera, shooting and editing the video.”
Junior Secondary Division Champion: Kowloon True Light School
Title of video: Comparing the Efficiencies of Microbial Fuels with Different Food Waste
Team members: Cassie Chan Tsz-lam, Cheung Ho-kei, Lam Tin-lok
Motivated by concerns over landfill overflow, the team aimed to find sustainable ways to repurpose food waste into energy. They consulted research papers and conducted week-long fermentations of various items – including apple and banana peels – to analyse starch and glucose content. Each fermented sample was tested for ethanol levels. “We followed full testing procedures using a multimeter and acidified potassium dichromate,” Ho-kei said.
When the voltage output fell short of expectations, the team used air pumps to increase the oxygen level and enhance the chemical reaction. “We incorporated testing into every stage of the experiment,” Cassie said. Despite facing unpleasant odours from some of the fermented mixtures, the team displayed remarkable commitment, recalling the experience with laughter.
“The major takeaway was realising how deeply chemistry is woven into everyday life,” Ho-kei reflected. “We’d heard of some of these discoveries through news reports, but this competition pushed us to explore how chemical processes power batteries.”
Their engaging video, featuring vivid storytelling, showcased this new-found knowledge with compelling details and encouraged viewers to reflect on their own waste, fostering a sense of community responsibility in sustainability.
