Carbon Emissions: Carl’s Carbon!

Understanding the negative impact gas-powered cars have on the environment empowers engineers to develop alternative modes of transportation. With the rise of electric vehicles on the market, different engineers that specialize in chemical, mechanical, and electrical engineering (and various other disciplines in engineering) can work together to design and develop car materials that are more sustainable and environmentally conscious.

After this activity, students should be able to:

• Describe the greenhouse effect.
• Recall the role carbon dioxide plays in the greenhouse effect.
• Recognize how transportation can affect the greenhouse effect.

A basic understanding of the atmosphere, gases, energy, and transportation.

Transportation is a way of getting from one place to another. What are some examples? [Ask students to volunteer answers in an open discussion. Use Google images to show various images of cars, trains, buses, planes, bikes, etc.] The most basic mode of transportation is walking.

What modes of transportation do you use to get to school? [Students may offer the following or similar answers: buses, walking, cars, carpooling, etc.]

Carbon emissions are the carbon dioxide released into the atmosphere by transportation. Carbon emissions are a result of burning fossil fuels for energy. What modes of transportation emit carbon dioxide? [Students should answer with any vehicle that emits gas—cars, steam-powered trains, airplanes, buses, motorcycles, etc.]

What modes of transportation do not emit carbon dioxide? [Students should answer with walking, biking, skateboarding, rollerblading.]

Why might it be harder to walk to school instead of driving a car? [Students should mention things like the time it takes for each, walking might be more tiring, the weather might be too bad for a walk, etc.]

How can we solve these problems? [Ask students to volunteer solutions for any of the answers they gave to the previous question. They might mention carpooling, using bikes instead of walking, using the bus on days with bad weather, etc.]

Some of the problems and solutions we just mentioned involve trade-offs. What do you think a tradeoff is? [Let students offer their ideas.] A tradeoff is a choice you make that benefits you in one way, but at the same time results in you losing another quality. For example, if you spend your allowance on a video game, you gain the video game, but you “lose” (by spending) your allowance and no longer have that money to buy something else.

Here’s another example: we might choose to drive a car because it is easier for us than to walk, but cars emit carbon dioxide. And carbon dioxide is not good for the environment.

We should think about these trade-offs more to understand why there are so many different modes of transportation and which ones are the best.

Let’s get started to learn which modes of transportation are better for our environment!

Background

The kind of transportation we choose can have a big impact on the environment. As engineers work to create more energy-efficient vehicles, students should consider why it may be hard for people to switch over to the current options available to them.

In this activity, students are introduced to the idea of trade-offs and why the choices we make every day can be significant. Students should recognize how many different modes of transportation exist and why we may choose one over the other.

Let’s help Carl make a decision about how to get to work!CopyrightCopyright 2022 OpenClipart, Public Domain, freesvg.org

Before the Activity

• Gather materials and make copies of the Carl’s Carbon Worksheet (PDF).

With the Students 

1. Divide the class into pairs or small groups to work together.
2. Set the stage for the activity by reading aloud the Introduction / Motivation section.
3. As a class, read and discuss the “Problem”, “Constraints (limits)”, and “Transportation Trade-offs” sections in Carl’s Carbon Worksheet (PDF).
4. Next, in the “Imagine” section of the Carl’s Carbon Worksheet (PDF), have students draw or write their thoughts on the best and worst forms of transportation and why.

• •  Have students share their ideas as a class.

5. For the “Design” section of Carl’s Carbon Worksheet (PDF), introduce and discuss each day’s transportation challenge.
6. As a class, go through Carl’s Trip Tracker table day by day to determine the best solution for Carl to get to work on time with the limits (constraints) he is facing.
7. Have a class discussion to determine the key constraint each day that Carl must overcome related to weather, cost, travel time, available money, and any health bonus considerations.
8. Get to a consensus as a class on the best way for Carl to get to work each day and circle the best choice that the class agrees on.
9. For the “Test” section of Carl’s Carbon Worksheet (PDF), calculate Carl’s total carbon cost for the week by adding each day’s carbon cost for the week. Circle Carl’s Carbon Footprint amount based on his travel decisions during the week.
10. Reflect on the process students used for making Carl’s transportation decisions based on the constraints he faced each day. Ask students if their thoughts on the best and worst forms of transportation have changed from their initial thoughts in the “Imagine” section.

Conclusion

When you have more people in the car or bus, the amount of pollution per person is less, that's why carpooling or taking the bus reduces your carbon footprint. Walking or using your bike is even better for the environment because there is no exhaust full of carbon dioxide. As the climate crisis grows bigger, engineers are trying to reduce the carbon footprints left by their designs. For example, more and more electric cars are being sold as engineers figure out ways to make them more efficient. Along with the growth in electric vehicles, many engineers are finding solutions to make it easier to switch over, like creating electrically charged roads. Now that you have learned how transportation can affect the greenhouse effect, would you try any of the transportation modes in the activity?

Pre-Activity Assessment

Discussion Questions: Ask the students and discuss as a class:

• What methods of transportation do you use to get to school? Do you ride in a car or on the bus often?
• Do you know if they use fossil fuels?
• What effect do gas cars have on the environment?
• Are there any alternatives?

Activity Embedded (Formative) Assessment

Guided Worksheet: Have students work together in small groups or individually on the Carl’s Carbon Worksheet (PDF). Once they are finished, have them volunteer to share their answers with the class.

Post-Activity (Summative) Assessment

Real-Life Application: Have the students create their own table similar to the one provided in the worksheet by using local weather, bus fare and gas rates, average travel times, and more to plan out their commute to school.

Making Sense: Have students reflect on the science concepts they explored and/or the science and engineering skills they used, plus questions or ideas they have by completing a modified Making Sense Assessment (PDF).

Prado, Luis. “Exhaust Gas on the Noun Project.” The Noun Project, The Noun Project, thenounproject.com/term/exhaust-gas/597970/