Hey! Where'd that come from?

I am referring to the time clock that was apparently mounted on the wall of my classroom.  As soon as we were done with our testing, it was as though my little friends clocked out for the day (like immediately...no standing around chatting about current events before eventually punching out).  And I totally understand.  It was a nice (although rainy) day.  We had worked our little Number 2 wielding fingers for three straight days.  They had done everything I asked them to do.  I was finished saying things like, "Fill in the circle of the answer you choose," and they were done filling in said circles.  I am relieved and exhausted all in one.