For most people, kites are simply toys, a way to have fun in the park or at the beach., but not Benjamin Franklin.

When he flew his kite in 1752, it became one of the most important experiments in the history of science. Franklin had been studying lightning for some time and wanted to prove that it was the same thing as electricity. He had planned to use a church steeple as a conductor for his experiment, but he got impatient. So he built a homemade kite from a few sticks, a handkerchief, and some string. Then, as we all know, he tied a key to the end and waited for the storm. Luckily, Ben only got a shock.

On National Kite Flying Day, celebrate by making the most of a windy day. But if you see storm clouds roll in, get indoors. Not everyone is as lucky as Mr. Franklin.