The Hong Kong No Air-Con Night 2011 was organized by Green Sense (環保觸覺) on 29th September. To support the activity, the school invited students and parents to shut down their air conditioners from 7:00 pm that night up to 7:00 am next morning. More than 400 parents of the school had promised to take the action. Since each family could reduce emission of 5.6kg carbon dioxide for 8 hours of air-conditioner use, a total of 2240 kg carbon dioxide could be reduced thanks to the efforts of our students and their family. We believe that each individual can play an active role in environmental protection and hope that such a practice can be kept on in the future.