Fighting germs with soap!

This week we are discussing noses. The jobs of a noses are smelling and 'snotting'. The latter leads to the big topic of germs.

Within a large discussion on germs, I explained that germs are everywhere. 
"Like Hashem!" Elchanan cheered.
"Is Hashem in the germs?" asked Naomi Bina. Theology and science at their best.

We discussed the best method of keeping germs away and staying healthy, involved washing our hands regularly. 
I regularly have conversations which go something like this: 
"Did you wash your hands?" 
"Yup!" 
"With soap?" 
"Uhhh..." 
Therefore we did a science experiment on germs and how only soap, and not water alone, fights germs. 
(Disclaimer: this experiment is actually about surface tension and not germs, but it illustrates the importance of soap). 

I poured water into a bowl and sprinkled black pepper on top. 
I passed the pepper around for everyone to smell. "This is pepper. We use it to season food. But for this experiment we will pretend it is germs." In turn, the students stick their finger into the bowl, and the germs/pepper sticks to them. 

Then we put a drop of soap on our finger and return it to the bowl. The germs/pepper magically run from soap! (It is really cool! Try it!)