I don't remember anything really dumb from my childhood off the top of my head, but funny enough the same dumbass thing happened to both my dad and to Meat Loaf when they were kids.
When they were younger they both played cowboys and indians (not together of course
)
My dad and his friend decided the game wasn't real enough, and so they took the suckers off the toy arrows and put them in a sharpener to make them nice and pointy.
Several thousand miles west, Meat and his friend had come to the same conclussion.
Meat took one to the forhead and stood there with the arrow sticking out of his head.
My dad took one to the eye.
He was very lucky not to lose it, and it made things more difficult when he had to have an operation on his eye a couple of years ago.
Luckilly the operation was a success.
Thinking about it, Meat is two years younger than my dad, and if you assume they were roughly the same age when it happened, there can't have been much difference time wise.
Just goes to show that kids on both sides of the Atlantic can be real dumbasses