Here are a couple of mine:
On my friend's birthday, "Let's all sing an off-key 'Happy Birthday.'"
My teacher attempting to draw the U.S:
Student: "Is that South America?"
Mr. D.: "Well..It was supposed to be the United States.."
Student: "Wow." And believe me, that was one ugly U.S. I guess you just had to be there..
My teacher has this background on the computer. It's this little island surrounded by ocean. Here's a conversation that went on between her and another student.
Ms. C: "Oh yeah, I live on that island."
Student: "Then where is your house?"
Ms. C: It's underneath that middle palm tree. There's a trap door.
Student: "Then is that your boat, too?" (There was also a boat in the picture

)
Ms. C: "No, that's Abby's dad, delivering me groceries." (Not her real name, but her dad worked at a grocery store.)