I work at a school!

So I had to go to the DMV today to get my license renewed. Fun stuff. What was once an infamously long wait in our area has been whittled down to less than 10 minutes. Not too bad. I always hate telling what the road signs mean...do I really have to say that the white and red triangle that says "YIELD" does indeed mean that one has to yield? Or do I need to prove that I know what yield means by saying "you have to wait and let the other people go first?" Whichever way I was on a roll until I got to the 3rd blank sign. It is yellow and has five sides, kinda pointing up. I said I didn't know what it was. The lady asked me if I was sure. I was thinking to myself that it really sucked and prayed that I would still get my license. Once I told the lady that I really didn't know she informed me that it was a sign for a school. What? Are you serious? I immediately laughed and informed her that I, the one who didn't recognize this sign, am a school employee and drive by these signs at least 3 times a day! Ironic, huh? So now I have until 2017 to forget this sign before my next sign test.