I taught a math remediation class tonight after school. I had a bunch of students who aren't in my daily classes, so I was meeting them for the first time.

Me: What's your name?
Student: Katie.
Me: Okay Katie, come on up here and do this problem.
Student: I don't know any Katies, my name's Katherine.
Me: Katherine, come up here.
Student: Who's Katherine?
Me: Okay, you have one shot to tell me what you want to be called for the rest of the program. Ready, go:
Student 1: Katie.
Student 2: Carlos.
Student 3: Pickle!

I really did call him Pickle for the rest of the day. 3 hours is a long time to refer to a child as "Pickle" without bursting into giggles.