I arrive late to class. I'm carrying a couple of camping chairs (folded up into their tube-shaped carry bags) because I came directly from my car, but I don't have my books and notes. Everybody is taking a test. I say that I'll be right back, I have to go to my locker and get my stuff. I go out into the hallway, which is lined with lockers, but I have to recollection of which is mine. I think the numbers should be familiar, but they aren't, all the lockers just look the same. I give up and carry my chairs back to the classroom.

The test is over, so I sit down at one of the student desks. The professor asks me to write "the force equation" or something like that on the chalkboard. I'm not sure what he means but I think it should be force-of-one-thing plus force-of-another-thing equals zero, and I get up to write that on the board, but another student apparently thought the professor was talking to him, and gets up ahead of me and writes an equation on the board. His is apparently correct, and is completely different from what I was thinking, something that looks quadratic.