As students enter the room, have the following question
on the board. Students should write it and a response in
the “if…then…” form of a hypothesis
in their science notebooks. “What is the relationship
between city size, temperature, and the amount of pollution?”
Ask students to share their ideas with the class, making
sure that all hypotheses have an explanation for their
ideas. (Quality hypotheses will refer to the previous
Tell students they will be visiting the computer lab
today (and possibly tomorrow). While they are there,
they will conduct a controlled experiment to see how
different variables affect the amount of pollution
or air quality. The better the air quality, the lower
the numerical value.
Take students to the lab and have them open the CO
Buildup City flash animation from Air Info Now at http://www.airinfonow.org/html/activities.html
5. Allow students a few minutes to become
familiar with the program before getting to work. This
will maximize their on-task time during the experiment.
Once students are familiar with the program have them
design an experiment that will test the effects of
only one of the two possible variables (time of day
and city size). Students should write up their procedures
and design a data table before beginning.
Once the procedures and table are complete students
may begin. (see Size Protocol and Time Protocol for
protocol for both experiments as well as possible data
When they have finished collecting data, have students
write a formal conclusion in their science notebooks.
What did they discover? What was the relationship between
the independent and dependent variable?
Students can now go back and repeat steps 6-8 controlling
for the other variable. This will give them a complete
picture. If you are pressed for time, you might
elect to have half the class control for temperature
(time of day) and the other half control for city
size (amount of CO released into the air). Advance
groups might carefully control both variables simultaneously.
When students have completed both experiments, bring
them back together in the science room. Have students
share their findings. Did all groups agree about what
was causing their results? Why?
Ask students to relate their findings to asthma. What
size city is best for a student with asthma? Why? When
is the safest time of the day to be outdoors? When
is the most dangerous? Why?
Have students write a brief paragraph about how they, or their families,
could help reduce their personal CO emissions.