Even as a kid, you notice some patterns in the calendar. Thanksgiving is always on a Thursday, Easter on a Sunday, your birthday seems to move around almost at random. One thing you probably noticed is that exactly one week after Christmas was New Year's day, so that if Christmas occurred on a Saturday or Sunday, cheating you out of a day off, then you'd get cheated in the same way on New Year's Day.
At least, that's the way I remember it happening, but I happened to look carefully at a calendar and noticed that in 1937, Christmas Day occurred on a Saturday, but New Year's Day was on a Friday. Was a law of the universe wrong? What cataclysm could have caused this to occur?
I give up, show me the solution.