In the "Cleaning the Air" activity, students use the engineering design/test/build process to create a model indoor air filter and then count and calculate the average number of particles collected. After they have tested their design they make a sales pitch presentation to their classmates highlighting the effectiveness of their design.
Resources provided include background information for the teacher and students, a student worksheet, a materials list, and instructions for setting up the testing apparatus. The activity should take 2-3 class periods. The experiment involves blowing fine particles such as pepper or sand with a hair dryer.
Teachers may want to include the previous activity in the Teach Engineering curriculum “I Breathe What?” https://www.teachengineering.org/activities/view/cub_enveng_lesson07_activity1. This lesson is reviewed in the NGSS@NSTA hub at http://ngss.nsta.org/Resource.aspx?ResourceID=756.
Another related resource in the Teach Engineering curriculum addresses air pollution, “The Air We Breathe,” which is available at https://www.teachengineering.org/lessons/view/cub_enveng_lesson07.