Make Germs Scatter Hand Washing Science Demonstration

Kids will be amazed at this simple hand washing science demonstration that reminds them visually that using soap when washing hands literally makes “germs” scatter.

Yes, dish liquid is great for washing dishes, but there are so many other fun uses for soap. In the classroom I loved using this quick science activity to demonstrate the importance of using soap while washing hands.

With this simple science demonstration you can give kids a vivid visual that will help them remember to use soap each time they wash their hands {hopefully!}.

And bonus! They’re also learning a little about surface tension along the way.

Watch the Hand Washing Science Demonstration Video

You can watch the full science demonstration in this short video.

When we did this demonstration I started by gathering a bowl of water, black paper, and dish soap. Then I asked the girls to talk with me about what they know about soap and why we use it.

After our chat I told them we were going to learn about how soap makes germs scatter, and I asked them to sprinkle some pepper into our bowl. (Don’t add too much or the demonstration will not work as well.) They observed how the pepper floats on the surface of our water, and I told them that was like germs on the surface of our skin.

Then we covered one finger with dish soap. Our container was full so we just dipped a finger in, but you could also squirt the soap on the finger or dip a finger into a smaller container with soap poured in it.

Now for the big moment! And it’s a fast one, so make sure everyone is watching. Stick that finger into the water in the center of the bowl if possible. And POOF! Those “germs” scatter to the edge of the bowl. It’s quick, but powerful and kids remember that moment. Afterward we talked about how the “germs” are afraid of the soap and what we can learn from this demonstration.

This was always a powerful message that stuck with my kindergarteners when I was teaching in the classroom, and so far it’s had a lasting impression on my own girls as well.

The Science Behind this Hand Washing Demonstration Activity

A note about why this happens:

Inquisitive little scientists might want to know exactly why this happens since the pepper isn’t really “germs.” Basically the demonstration has more to do with the soap and water. The pepper just allows us to actually see what is happening. When soap is added to the water it lowers the surface tension of the water causing the water molecules on the surface to “scatter” or pull away from the point where you added the soap.

More Hand Washing Tips and Resources

Don’t forget a helpful hand washing song!

Help kids remember to wash long enough with a fun hand washing song for kids. Over on Fun-A-Day you can grab the free printable pictured below and see a collection of YouTube videos about hand washing to choose from.

Teach curious kids the history of hand washing!

Max Brooks shares the history of hand washing over on History.com. There’s even a free printable activity that includes another fun science experiment about germs.

Get help teaching 13 key classroom procedures

We know there are more routines to teach in the classroom than hand washing.

This 605 page classroom procedures bundle is full of step-by-step instructions for everyday routines children engage in at school, along with helpful tips and guidance to help you teach clear and detailed steps for 13 key classroom routines to your students.

As a bonus, we’ve added social distancing and online learning routines to accommodate today’s unprecedented learning environment. 

Also available on Teachers Pay Teachers.