September 14, 2009
This lesson is a twist on an AIDS lesson I saw. I explain that people can carry flu and cold germs and can infect other people even if they themselves don't feel sick. You’ll need flour, baking soda, vinegar, plastic baggies for each student, and some trays.
I prepare a small baggie with two tablespoons of flour for each student in my class — except that one bag also contains one teaspoon baking soda. The students are not told what is in the prepared bags. Everyone must give two teaspoons of their powder to someone else. After the recipients have mixed their powder, they give two teaspoons of powder back. After everyone has traded at least four times, the bags are placed on trays to insure no one is being singled out and teased. Here are some questions to explore with the students: I ask if anyone feels any different or feels sick, and then I ask how people actually ‘trade germs?’
Next, I explain to students that we started this activity with one person having the flu germ — the baking soda — and that now we’ll test to see how many people carry the germ after they’ve ‘traded.’ Add vinegar to each of the samples; the bags with baking soda flu germs will have a chemical reaction. Depending on the grade level, students can compute percentages, proportions, etc. Lastly, I ask students what we can do to prevent picking up germs from others.
The flour, baking soda and vinegar are safe enough to dispose of in the trash.