I don't know what they're called.  They're like paper dolls except they aren't made of paper but of something rubbery instead.
You peel them out of a book.  Some of them are quite small.  They are not stickers exactly but they stick to things; not to yourself, generally speaking, except possibly your fingers.  They are re-usable too.  You can rearrange them.

On a rainy summer day you can stick them on the window overlooking the lake, and they seem to float there above the dock and against the raindrops, hovering in the woods on the other shore.

Last summer I watched a very clever young girl who was not yet three spend a peaceful part of an afternoon methodically decorating the rainy view with these tiny little people and their accessories.  Last summer she was still in her cave-man phase -- expressing the core of a thought or an emotion, desire or displeasure (as circumstances might demand) in intermittent, efficiently compact sounds.  Her older sister was being the articulate one, delighting everyone with her gift of gab and so, as you might imagine, why compete.    

What are they called? I asked, hoping to be helpful.  What are they doing?  Are they flying through the air?   

Grunt.