Who said it's not polite to stare?

When I picked my son up from daycare yesterday, he was excited to tell me that he had a staring contest with a big kid on the schoolbus: "He blinked a lot and I didn't!" I asked him if he knew the boy, and he said no. I asked if they talked before or just started staring. He said they just started staring. He said when the bus got to my son's stop, he and the boy said "Bye". Those were the only words exchanged.

I wonder at what age a wordless staring contest with a stranger becomes weird instead of fun? :-)

Or maybe it's still fun, and no one told me. Go ahead and try it and let me know. Heh.