Intentional play is the best way to learn. Email from a Souns mom:

We decided to wash the Souns with shaving cream and my daughter loved it.  I started off by sitting with her putting the shaving cream on a rubbermaid container top.  We both spent time drawing Souns in the shaving cream then I left her alone to play.  

She was quite fascinated with the shaving cream and she spent tons of time cleaning then organizing the Souns on the side of the tub.

I had to take some pictures of this wonderful experience!!  Thought you would like to see some. The pictures are in order to see the start and finish of her project.