Small White Dot

A kindergarten class had a homework assignment to find something exciting and relate it to the class the next day.

When the time came to present what they had found, the first little boy called on walked up to the front of the class and with a piece of chalk, made a small white dot on the blackboard, and then sat back down.

Puzzled, the teacher asked him what it was. 'It's a period,' he replied.
'I can see that,' said the teacher, 'but what is so exciting about a period?'

'I don't know,' he said, 'but this morning my sister was missing one, my Mom fainted, my Dad had a heart attack and the boy next door joined the Navy.'