Period...

A teacher of kindergarten class gives homework to find out about something exciting and tell it to the class the next day. Next day, the first little boy called on to the front of the class, and, he said one word period.
Puzzled teacher asked him just what it was.
“It’s a period,” said the little boy.
“Well, OK,” she said, “but what is so exciting about a period?”
“Damned if I know,” said the little boy, “but this morning my sister was missing one, dad had a heart attack, mom fainted, and the man next door shot himself.”