Sackhumvit Trust completed a module on ozone depletion with 9th standard students associated with Dream School Foundation’s (DSF). Sackhumvit Trust conducted this module as part of an after-school tutorial program offered at DSF’s academic resource centres in Yeshwantpur and R.T. Nagar. This module is the second in a series focusing on environmental issues associated with urbanization.
Ozone Module Learning Objectives
Sackhumvit Trust utilized materials from the United Nations Environment Program (UNEP) for this module. UNEP has created a series of worksheets, activities, comic books, and videos based on the fictional character, Ozzy Ozone, to educate youth on the sources and consequences of ozone depletion. The module started with a cartoon video illustrating how ozone depletion enables U.V. radiation to reach the Earth’s surface and harm human-beings. The video was effective at drawing student’s attention to the importance of ozone depletion, and students were quickly attracted to the character of Ozzy Ozone.
The video was followed by a series of worksheets and activities included in UNEP’s High Sky: Ozonaction Education Pack for Secondary Schools. Students learned about the layers of the atmosphere, and their specific properties and roles in fostering life on Earth. Students studied the ozone layer in greater detail, and how its dramatic thinning, especially over Antarctica, has been coined as the ‘Ozone Hole.’ Students then studied the chemical properties of ozone. This was useful in explaining how ozone absorbs and reflects U.V. radiation to prevent it from reaching the Earth’s surface. It was explained that U.V. radiation supplies the necessary energy for creating and breaking down ozone, thus establishing a chemical equilibrium that keeps the amount of ozone in the stratosphere constant.
This was followed by activities exploring man-made and natural sources for ozone depletion. Students studied the chemical process by which Chlorofluorocarbons (CFCs) and Hydrochlorofluorocharbons (HCFCs) breakdown ozone, which was facilitated by a useful diagram in the High Sky workbook . Students learned that the increased emission of CFCs and HCFCs in the stratosphere has disturbed the natural equilibrium of the ozone layer, resulting in a drastic thinning of the ozone layer. Students also completed a survey determining if their schools and DSF’s resource centres use materials made from or containing ozone depleting substances. Students concluded that their schools and DSF’s centres were relatively ozone-friendly, with the exception of their use of polystyrene cups.
Students reviewed health affects of U.V. radiation which was facilitated by a puzzle that differentiated the three types of U.V. radiation (U.V.-A, B, and C) in terms of wavelength, reaction with the stratosphere, and their effects on human health and plant life. Students were also introduced to the creation of ground-level ozone by smog in lower levels of the atmosphere, and how this is dangerous for human health and plant life.
Students then studied the U.V. index developed by the World Health Organization and tracked the ratings of Bangalore city from an online weather site; students were shocked to see the city consistently reported an index value of 11 (extreme)! This was followed by a review of conditions that increase our risk to U.V. radiation exposure, such as time of day, time of the year, location, elevation, reflection, and weather conditions. Students then discussed how they can limit their contact with U.V. radiation, and possible action steps to be taken by their local community, governments, and international bodies to prevent ozone depletion.
Ozone Module Highlights
Certain activities in UNEP’s High Sky workbook were particularly effective at raising awareness on ozone depletion, and resonated strongly with our students:
Students adored the Ozzy Ozone cartoon figure, and thoroughly enjoyed UNEP’s video and comic book productions. It would be worthwhile for UNEP to conduct a competition where students submit comic strips of Ozzy Ozone combating ozone depletion in their own country. This would enable UNEP’s content to appeal to a wider group of students, while encouraging students to apply their knowledge on ozone depletion in a creative manner.
The coded message from Ozzy Ozone concerning properties of the ozone layer, the discovery of the Ozone Hole over Antarctica, and how ozone depletion is impacting nations all over the world was extremely popular. Students enjoyed learning a secret code and were fully absorbed in revealing Ozzy Ozone’s message.
Students enjoyed the puzzle activity where they had to piece together the entire spectrum of radiation created by the Sun. This activity was useful at demonstrating how U.V. radiation is just one component of the entire range of light or energy that influences life on Earth. This activity also related to the light unit covered in the 9th standard science syllabus of students, hence inspiring Sackhumvit Trust’s module on properties of light.
The numbers game reviewing conditions that create ground-level ozone was a popular activity. However, the instructions for this activity were unclear and consequently obscured the activity’s learning objectives. Students were more focused on solving the number puzzle, as opposed to understanding how various factors can create ground-level ozone. This is because they were not sure what all the numbers represented.
The diagrams illustrating ozone equilibrium and how ozone depleting substances disturb this chemical process were particularly useful. As students often struggle to understand the change taking place in chemical equations, it was helpful to visualize the process of ozone creation and destruction.
There were additional activities in the High Sky workbook that we could not complete due to time constraints. Moreover, students were also unable to participate in certain activities due to their limited knowledge of English. This includes recreating the Montreal Protocol summit to advise policy on ozone depletion in sessions of 5-7 of the High Sky workbook. Students also started to lose interest in studying ozone depletion as it did not relate to their coursework at school.
Based on these observations, our volunteer teachers decided to focus on basic knowledge of ozone depletion (hence our coverage up until session 3 of the High Sky workbook), and transitioned to exploring properties of light. This has enabled us to cover concepts relevant to ozone depletion in the context of the science syllabus of our students. We found that it is more effective to raise awareness on ozone depletion through supplemental activities that complement the school work of students, as opposed to teaching this subject entirely on its own. We will continue to complete activities in the High Sky book in this manner, especially those in session 4 that explain the difference between ozone depletion and global warming. These exercises relate to the carbon cycle reviewed in the biology syllabus of our 9th standard students.
Sackhumvit Trust would like to thank DSF for enabling us to work with their students as part of its after-school tutorial program. We are also grateful to UNEP for sharing its learning materials and hope that our review of this module has been constructive.