Clean Hands

Submitted by Tammy Knight from South Walker HS 

 Materials: non-toxic washable markers in dark colors, hand soap, running water in a sink or outdoors from a hose, paper towels 

 This experiment demonstrates the importance of using soap as well as water to get hands really clean. Remind children that hand washing removes germs with soap and water. Demonstrate how to wash hands correctly by applying soap and rubbing hands together under running water. Using a dark washable marker, draw a smiley face or a simple germ on the back of each child's hand. Give each child a dry paper towel and see if they can remove the marker "germ" just by rubbing. Next, divide children into two groups. Give each child in the first group a squirt of non-toxic hand soap. Now all children rub their hands under running water while you sing "Happy Birthday" (or count up to ten) together. When the song is over, turn off the water and have each child check his or her hands. 

Whose germ is completely gone? How many children who used soap still have germs (or parts of germs)? What about children who used water and no soap? If some children still have part of a germ, start the water again and sing the song (or count) a second time. Turn off the water and check again for germs. Compare to see which group of children – soap or no soap – eliminated germs first. 

Talk about the results. Is it better to use soap, or just water? Is it better to wash hands quickly, or take more time? 

Modifications and Extensions: (1) Allow children to draw germs on their own hands. (2) Talk with children about different kinds of cleaning. How do clothes get clean? Dishes? Pets? Toys? Hair? Are all these kinds of soap the same? (Do they look the same, smell the same, sound the same...) What would happen if they used hand soap to clean clothes, or shampoo to clean dishes?