Pumping out carbon dioxide (CO2) and other greenhouse gases is poisoning the atmosphere. Your carbon footprint indicates how much of it is down to you. It's a powerful message for the young: know the size and effect of your footprint.
The average British carbon footprint is just under 11,000kg of CO2 a year, but scientists warn this must be reduced to 2,500kg to stop global warming. Show students the Wikipedia table and map comparing emissions from different countries (http://en.wikipedia.org/wiki/List_of_countries_by_carbon_dioxide_emissions_per_capita).
The science behind CO2 in our life cycle is fascinating. Earth has developed a delicate juggling act whereby the amount of CO2 entering the atmosphere through respiration and decay is balanced by the CO2 absorbed by plants. The balance has been overturned through the burning of fossil fuels and the consequent release of CO2. The BBC weather pages provide an accessible explanation: www.bbc.co.uk/weather/features/gases_carbondioxide.shtml. Illustrating the process would make a good introduction to the topic for students. Younger students can explore an animated explanation of the carbon cycle at www.epa.gov/climatechange/kids/carbon_cycle_version2.html, while older students can investigate the cycle at www.purchon.com/ecology/carbon.htm.
Challenge students to calculate their own carbon footprint. An attractive calculator is provided by BP (www.bp.com/extendedsectiongenericarticle.do?categoryId=9008204&contentId=7015209&BPLinkTrace=1604280000). A little homework beforehand, such as establishing their household's type of heating, working out journeys travelled, and so on, will make the calculations more accurate. Provide each student with a footprint template on which to record their level of CO2. These could be displayed.
Their next challenge is to work out what steps will shrink this. Set them thinking about solutions by taking part in Tear Fund's climate change pentathlon (www.tearfund.org/Campaigning/Climate+change+and+disasters/pentathlon).
Even seemingly simple decisions like what to eat can have an impact on our footprint. Direct students to an article that works out the carbon footprint for burger consumption in the US, which could account for as much as 150,000 tonnes of carbon (www.openthefuture.com/2006/12/the_footprint_of_a_cheeseburge.html). Use this article to help students identify the factors influencing the footprint (such as production, selling and cattle methane production).
Carbon offsetting is a way of compensating for CO2 emissions by buying credits in offsetting projects, which prevent or reduce CO2 emissions elsewhere, such as through the planting of trees. Students can read an explanation of carbon offsetting at Defra (www.defra.gov.uk/environment/climatechange/uk/carbonoffset). Examples of offsetting projects in the developing world can be found at Climate Care, through a range of short videos. Carbon capture and storage is seen by some as a future solution. Students can find out more at www.guardian.co.uk/life/thisweek/story/0,12977,1506967,00.html and see diagrams of what it might be like at www.co2capture.org.uk.
Many businesses are now taking steps to reduce their carbon footprint. The BBC has an interesting range of video reports focusing on the issue, including a report on M&S's pledge to become carbon neutral (http://news.bbc.co.uk/player/nol/newsid_6270000/newsid_6275700/6275717.stm?bw=nb&mp=wm).
Encourage students to look at their local CO2 picture. An Office for National Statistics report reveals that household emissions are rising (www.statistics.gov.uk/downloads/theme_environment/Impact_of_households_final_report.pdf).
Shrink your footprint
Finally, return to shrinking the students' individual carbon footprints. Direct Gov has ideas that focus on cutting down on energy use (www.direct.gov.uk/en/Environmentandgreenerliving/index.htm).
Get students to create a campaign focusing on one aspect that will benefit the school's footprint, such as using less paper, walking to school. Encourage students to create posters for their school and their local area (library, shops) on how to shrink a carbon footprint. The Carbon Trust has business ones that may provide inspiration: www.carbontrust.co.uk/energy/startsaving/posterfacts.htm. Teachers and students will find a complete KS3 lesson on carbon footprints at the Guardian's online daily newsdesk for schools www.learnnewsdesk.co.uk
Key stage 2
Citizenship & PHSE 2a, 2f-h; English (En1) 3a-f; (En2) 3a-g; (En3) 2a-f; Geography 2c-d, 3a-g, 5a-b; Science (Sc2) 5a
Key stage 3
Citizenship 1f-i, 2a-c, 3a-c; English (En1) 3a-e 4a; (En2) 1a-d 4a-d; (En3) 1e-k; Geography 2c-d, 3a-e, 5a-b; Science (Sc4) 5a-c
Key stage 4
Citizenship 1f-j, 2a-c, 3a-c; English (En1) 3a-e 4a; (En2) 1a-d, 4a-d; (En3) 1e-k; Science single (Sc4) 4b, double (Sc4) 5a-b
English (levels C-F); Environmental studies: social subjects (levels C-F); Environmental studies: science (levels C-F)