Duh

The new overhead projectors that were installed in our classrooms before break have speakers installed in them.  Which is great, except that you can't use the speakers without also having the projector on.  Fortunately, you can freeze the screen so you can listen to something and still use the computer without the kids seeing what you are working on.  So I usually freeze the screen on my homescreen. which looks like this:

Student 1:  Is that a beaver?

Student 2:  No!  Only sloths read books.  Beavers just build dams.  You should know that.

Me:  *mouth opens and closes in fish-like manner*