This module helps students learn about environmental
issues in preparation for designing their own environmental
solution in Chapter 4. In Chapter 1, students learned about
garbage and the environmental concerns related to garbage. They
continue learning about environmental issues in this chapter
using air pollution as a context.
In the Engage activity, What Is In the
Air?, students express their current conceptions about what air
is. They then construct pollution detectors and watch a
demonstration to draw out their ideas about air pollution.
In the Explore activity, Detecting Air
Pollution, students learn about the six major types of
pollutants that contribute to air pollution. They also learn
some of the sources for these pollutants and the factors that
may lead to higher levels of the different pollutants in the
atmosphere.
In the Explain activity, Why Is Air
Pollution a Problem?, students focus on the consequences of air
pollution. These consequences include harmful effects on
people’s health and damage to the environment.
In the Elaborate activity, Technologies
to Reduce Air Pollution, students consider four different
technologies that address issues related to air quality. Each
technology presents different benefits and costs.
In the Evaluate activity, The Light
Goes On, but Which One?, asks students to use what they have
learned about air pollution and costs and benefits to consider
three options for a technological solution. In this case, the
lightbulb itself is not the direct issue. However, when
considering benefits and costs, students need to think about how
much energy the different lightbulbs use, which influences how
much electricity needs to be generated. It is the power plant
that produces the electricity that is a very significant source
of air pollution.
Students may harbor misconceptions about the material they
will be studying in this chapter. We list some of these
misconceptions (Driver, Squires, Rushworth, & Wood-Robinson,
1994; American Association for the Advancement of Science, 2001)
in this section. Do not take time to go through them as a list
of lecture topics for your students, but rather use them to
inform your teaching as they emerge. Many activities included in
this chapter work to expose misconceptions and help students
develop better mental models.
Some common misconceptions include:
- Anything natural is not pollution. Air
pollution can come from either natural or human-made sources.
Natural sources can include dust, soil, soot from forest fires,
and ash from volcanic eruptions.
- Biodegradable materials are not pollutants. An
air pollutant is any substance that is added to the air in
harmful amounts. Although biodegradable materials may, in
general, be less harmful than other chemicals, they could still
cause problems.
- Oceans are a limitless resource. As scientists
learn more about air pollution, they are finding significant
impacts on all parts of the environment. One of the concerns
about pollution, including air pollution, is that it may lead
to a decrease in biodiversity.
- Harm to plants is not an environmental problem.
Sometimes, students think only about impacts on animals,
including humans. Air pollution, especially ozone, can have
drastic effects on plants, damaging leaves, inhibiting growth,
and reducing their capacity for photosynthesis.
- The addition of ozone to the atmosphere is
beneficial because there is an ozone hole. It is important to
make a distinction between the ozone that is very high in the
atmosphere and the ozone added near Earth’s surface. The
ozone that is high in the atmosphere is very important to life.
It protects Earth from the Sun’s harmful ultraviolet rays.
The ground-level ozone is a major pollutant that forms when
emissions from sources such as cars, power plants, chemical
plants, and refineries react chemically in sunlight.
Ground-level ozone can cause or exacerbate health problems and
damage the environment.
Another misconception that people have about air pollution
is that they can move away from it, and that if people move away
from cities, where the air pollution is greatest, they do not
have to worry about pollution’s effects on their health.
People tend not to recognize how far air pollution can spread.
Another health-related misconception that people have about air
pollution is that they believe pollution doesn’t affect them
if they are healthy and don’t have any health
problems—especially problems related to their lungs.
For several of the activities in the chapter, you will
need only 24 hours advance notice for preparations. The
following two investigations might require additional
preparation time:
- Explore: for collection of materials and preparation of
the demonstration and sample particle collector
- Explain: for collection of materials
See the Advance Preparation sections of these activities
for details on the necessary preparations.
