Learning module on ozone depletion

 

 

Aim

 

To provide teachers with the background, materials and direction to effectively teach the subject of ozone depletion.

 

Learning objectives:

        Students should ... 

• understand the basic causes of ozone depletion and the ozone hole.

 

• be able to explain the role ozone depletion has on Australia.

 

• be able to assess the important factors that determine the risk of skin cancer.

 

Background:

Recent studies indicate that Australian students have misconceptions about ozone depletion and how it affects Australia.  Although Australian students share concerns about the environment, evidenced in a survey which showed that almost 70% of Australian students viewed protection of the environment as the most important problem in Australia [Connell et al., 1998] , an understanding of ozone depletion in Australia is not yet evident in Australian schools [Cordero 2000].  .In particular, a majority of students incorrectly believe the ozone hole is over Australia, that the ozone hole occurs during summer, and that ozone depletion is directly responsible for Australia’s high rate of skin cancer.    

It has also been reported that teachers as well may have misunderstandings concerning ozone depletion, and thus the effective teaching of these subjects may require special effort [Khalid, 1999] .  In fairness to teachers, environmental issues such as ozone depletion and global warming are complex subjects, and current theories explaining these issues change quickly.  In addition, there also seems to be a lack of well designed teaching materials suitable for K-12 cirriculum [Meichtry, 1993] .   

Based on previous studies, it seems clear that two approaches towards improving student understanding of these environmental issues should be taken.  First, teacher understanding of these issues must be improved through better teacher resources [Lawrenz, 1986] .  This has been addressed through the development of teacher-based notes accompanying each lesson.  These materials aim to both help teachers in presenting of the material, and to help teachers develop a more solid understanding of the subject themselves.  Second, better teaching and learning activities should be developed that utilize strategies in changing student misconceptions.  Student misconceptions have been found to be highly resistant to change or alteration, at least through traditional teaching methods which focus on surface learning approaches [Groves and Pugh, 2000] .  Thus, a set of teaching materials was designed using conceptual change teaching strategies including visual diagrams to explain key concepts, and student-centered learning activities. 

Note:  For more information on Australian students misconceptions see:

• Cordero, E., Misconceptions in Australian students understanding of ozone depletion, Melbourne Studies in Education, 41, 85-97, 2001. (size:144k)

• Cordero, E., Is the ozone hole over your classroom?, Australian Science Teachers Journal, 2002. (size:  193k)

 

Methodology:

 

This module includes four lessons each focused on a particular aspect related to ozone depletion.  Included within each lesson are background materials, key learning figures and learning activities.  The background materials are designed primarily for educating teacher on the basics of ozone depletion, ultraviolet radiation and skin cancer.   The aim of the background materials, which are presented as PowerPoint overheads, is to provide teachers with ample information to feel comfortable and knowledgeable in the teaching of this subject.  The key learning figures include discussion questions and are designed to be used as teaching tools.   It is up to the individual teacher as to how they want to present the materials to their students.   Either directly using the provided PowerPoint overheads, or through discussion questions using key figures, teachers may find value in each depending on the student level and amount of time available for this section.  An important component to each lesson is a learning activity, aimed at challenging student previously held misconceptions about ozone depletion or skin cancer.  Finally, both pre and post ozone quizzes are provided to help both the teacher and student evaluate their own learning.

  

Materials needed:

 

Access to the internet to download materials (for teacher only; this module is not internet based).  Note:  materials total a 6 megabytes and thus may download slowly depending on your connection speed.  

 

Recommended:  

 

Access to Microsoft PowerPoint and Microsoft Word. 

 

Overhead projector,  computer data projector or hard copy handouts to for teaching with learning diagrams.

 

Paper and pen/pencil for activities.

 

Provided teaching and learning materials:

 

    

1)      Lesson 1:  "Ozone and UV radiation"

a)      Background:  Basics on the ozone layer and ultraviolet (UV) radiation. 

b)      Learning Diagrams: Ozone Bucket, Good Ozone/Bad Ozone, UV Radiation Today.

c)      Learning Activity:  Ozone concept maps.  Students develop concept maps using provided list of terms to explore their own understanding of topics related to ozone and UV radiation. Group work and discussion encouraged.

2)      Lesson 2:  "The Antarctic Ozone Hole"

a)      Background - History and basics on the ozone hole.

b)      Learning Diagrams: Ozone Hole Yesterday and Today, Ozone Hole Animation and Ozone Hole Recipe.

c)      Learning activity:  Examining ozone variations in different cities.  Students use real ozone data to answer questions about ozone levels over different cities, and to study the location and timing of the ozone hole.   Group work and discussion encouraged.

3)      Lesson 3:  "Ozone Depletion, Skin Cancer and Australia"

a)      Background:  How does ozone depletion affect Australia and why does Australia have such a high rate of skin cancer?

b)      Learning Diagrams: Australia- A High UV Environment and Ozone trends and Australia.

c)      Learning activity:  Skin cancer risk identification.  In groups, students answer questions about skin cancer risk based on provided UV maps, and understanding of the important risk factors.  Aim of activity is to challenge student ideas about the link between ozone depletion and Australia's high rate of skin cancer.

4)      Lesson 4: "Ozone Depletion:  The future?"

a)      Background:  What is being done about ozone depletion and what will happen to the ozone layer in the future?

b)     Learning Diagrams:  Ozone Hole Getting Bigger?, Ozone Depletion Trends.

c)      Learning activity:  Ozone concept maps revisited.  Students are to work with their earlier concept maps and add new terms such as ‘ozone hole’, ‘skin cancer risk’ and ‘ozone depletion’.  Aim is for student to revise on prior learning, and explore the interrelationship between more advanced concepts.  

Pre and Post-quizzes: To assess student understanding of the topics, both before and after ozone module.  Useful for exploring how student thinking changed over the module. 

 Note:  These materials are designed in a flexible manner, since they could be used for student from year 7 through first year university.  Some topics may not be appropriate for your particular student.   Teachers are thus encouraged to take and choose what they feel is useful for their own environment.  The learning activities are designed to take less than one hour each, depending on the level of discussion.  

 

Assessment

 

Although two quizzes (pre and post) have been included in the materials, the lessons may work better when coupled with some type of assessment, even if it’s minor.   Experience and research has shown that assessment is a prime motivator in student activities, and so suggestions for assessment strategies are provided with the activities.  

 

Downloading word and powerpoint materials:

 

Hypertext versions of the materials are available above.   However, it may be more convenient to download the original PowerPoint and Word files below.  To save the PowerPoint or Word file, right click the file and choose 'save to disk or save target as'.  Then, save the file on your own hard drive, and run when you wish.    

 

Note:  When viewing PowerPoint files, notice the  corresponding 'notes' attached to most graphics.   In addition, Background2  has an animation (860K) which may download slowly.  

 

Important:  The html version of the PowerPoint files can only be viewed using Internet Explorer 5.0 or later or Netscape 6.0 or later.  .

 

1. Lesson 1:  (PowerPoint file: background1.ppt  and word file:  learn_act1.doc)  
2. Lesson 2:  (PowerPoint file: background2.ppt  and word file:  learn_act2.doc)  
3. Lesson 3:  (PowerPoint file: background3.ppt   and word file:  learn_act3.doc)  
4. Lesson 4:  (PowerPoint file: background4.ppt  and word file:  learn_act4.doc)  
5. Learning Diagrams (PowerPoint file: learning_diagrams.ppt)
6. Pre and Post ozone quizzes:  (Word file: Quizzes.doc)