There are particles in the air that we can not see. Most particles do not harm us. We will go outside to observe an activity. Teacher attaches a white sock to the exhaust tailpipe of a car. Parent turns on the car and lets it run for just a couple of minutes.
Students observe only.
Remove the sock. The sock will have black particles attached to it. Return to classroom. In groups of four, create a collector for air particles. Lightly coat vaseline on white handkerchief.