The Germy Potato Experiment is designed to teach students about the importance of washing their hands through observation. To do this experiment, you will need three potatoes, hand soap and three plastic bags large enough to put one potato in each.
The Germy Potato Experiment
The first potato will be the control. After washing your hands hands and the potato, peel the potato and put it in a plastic zip lock bag without letting it touch anything else. The idea here is to keep all germs from touching the potato. Label this bag number one.
The second potato will be the germy potato. It is best to introduce this potato after recess. When the students come in, have the second potato washed and peeled, then have each child handle it before putting it in the second zip lock bag. Label this bag number two.
Then have the children wash their hands with soap and water for 30 seconds (sing the ABC’s to make sure they wash long enough). Once they have thoroughly cleansed their hands, wash and peel the third potato and have them handle it before putting it in the third plastic zip lock bag. Label this bag number 3.
Now have the students hypothesize: what will happen to the first potato? The second potato? The third potato? The students should draw and/or write daily observations about changes in the potatoes over the course of one week.
After a week, look at your potatoes and compare the results to your hypothesis: did what you think would happen actually occur?
Understanding the Potato Experiment
The control potato should look relatively clean and unchanged after one week. This is because it was not exposed to many germs.
The second potato is the germy potato and should have grown multicolored patches and look rather gross. This change is from the germs that the children had on their hands when they touched it. This shows the transfer of germs from one object to another on contact.
The third potato should hopefully look similar to the control potato. The germs should have been washed off the children’s hands before they touched the potato, but since we cannot kill every germ, so there may be some growth on this potato.
If something seems to go wrong with your experiment, allow the students to think through the process and see if they can figure out what happened. For example, if you accidentally drop the third potato on the floor, allow the experiment to continue without changing anything, and in the end, the third potato, supposed to be clean, will actually be more colorful and germy than the second “germy” potato.
You may be interested in more science lessons, including raising a tadpole, making flubber, and learning about static electricity.
Jennifer Wagaman - Jennifer is a mother of 2 and has both public, private and administrative experience in the education field.
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