…or stupid kid tricks. The object is to achieve the maximum number of seconds before the glass falls off.
This could also be classified as ways to avoid your homework.
My cat likes to play with a shaker egg. Sometimes I’ll balance it on her when she’s lounging around; she just sort of rolls her eyes, makes the egg fall, and smiles. Obviously one of us doesn’t get it.
I suspect that what you don’t get is that “smile” in human means “bares her fangs” in cat. 
(I’m bilingual; you should see what I can say with my ears.)
Oh, she does that, too, on occasion. 
But it’s a real smile; more of a Mona Lisa thing.
I wonder if that trick works on birds that weigh 5 ounces?
What about rats that weigh half a pound?
Or snails that weigh less than an ounce? 
looks for somebody’s dog to steal and puts a glass on its head