When I was in grade school, my teacher did a really simple pepper experiment with us to teach us about surface tension. Water has a surface that lets light things float on top, and when you add something dense, like soap to it, it breaks the water tension, and the pepper shows it well because the water will move away from the popped area and the pepper goes along with it.
All you need is:
1 drop of dish soap
and a bowl of water
1. Take your bowl of water and sprinkle the pepper in (as you can see in my photos my son added a whole lot, we were sneezing for five minutes!)
2. Take your soap and gently squeeze one drop into the middle of the bowl.
3. Watch it disperse instantly, your little one will be amazed.
Since water is transparent, most lessons involving it can be confusing to a small child because it’s hard to imagine, with this my son instantly understood how it all worked.