Terry M. Bella
This section is intentionally brief as the focus of these units is to present content. Below I have included a few activities that are simple to do in class and have been received well by students.
Classroom Activities: Carbon Cycle Map
Set up the room in stations for the reservoirs and number them 1 through 12. You will need to break down reservoirs more than this unit has done. For example, categories such as “land animals” and “land plants” are used. You want to have 12 stations so that students can easily use a pair of dice to determine their movements. Assign pairs or small groups of students to start at different reservoirs. Record the starting reservoir and roll the dice. Move to the corresponding reservoir and record. The students then must determine what processes had to take place for carbon to move from the first reservoir to the next. Have them repeat this ten to twelve times in the period with their ending reservoir being pre-determined as it should be the same as the starting reservoir. Have students make a poster or other visual representation of their pathway and present it to the class. This will take two or three class periods.
Classroom Activities: Converting Watts to Carbon
Through the use of a simple calculation it is interesting to determine how much carbon is produced through the use of everyday electronics. Using an accepted conversion of 2.3lbs of CO
2
per kilowatt hour and then adjusting for just the carbon by dividing by 3.667. This conversion standard is based on the use of coal.
This is easiest if students pick items that operate for lengths of time. For example, a microwave has high energy consumption but in general it is only run for a few minutes a day. This makes the microwave a poor choice for this activity. Conversely, a computer or TV will be operating for hours and the numbers will be more concrete.
Find the wattage of the item of interest and multiply by the number of hours of operation. Divide this answer by 1000 to convert to kwh. Multiply by 2.3lbs/kwh to determine the mass of CO
2
emission. Divide by 3.667 to determine the mass of carbon.
Classroom Activities: Density of Carbon Dioxide
This activity helps to illustrate how dense carbon dioxide is which in turn helps students to make a connection to its greenhouse gas nature. Thought the reason that carbon dioxide is a greenhouse gas is quite complex and beyond the scope of the ninth grade, the students will remember that carbon dioxide is heavy and dense. You can create some carbon dioxide gas and pour it over a candle, extinguishing the flame.
You need a tea candle, lighter, beaker, baking soda, and vinegar. Light the candle. Add 15ml of vinegar to one teaspoon of baking soda in a 250ml beaker. Allow the fizz to rise and fall. Gently lift the beaker and with slow pouring action you can pour the carbon dioxide onto the flame. The flame will go out because of the lack of oxygen as it is covered in carbon dioxide gas. Do not pour liquid onto the flame, only the gas. You cannot see it. Do a trial run before doing this with the class.
