[davidcalloway]

I know this is nitpicking and perhaps a dumb thing to say, but in my view the simple case of drink spilling does not apply.

Have you been around children who spill a drink? The ones who experience high levels of stress bury their heads and treat it as a catastrophe, waiting for someone else to clean it up and soothe them.

Those who treat it as no big deal are more likely to clean it up.

And being more careful only grows slowly with age. Oh, and using heavier glasses btw. It's way better to give kids real glass for drinks and tolerate the occasional breakage than to have constant spilling with light plastic cups.

[caseyy]

I think you might be overthinking it. Kids learn to prevent bad things from happening. They learn it so well that sometimes they also learn much helplessness.