School Follies

 Andrew recently started doing some first grade school at home.  He's doing some reading lessons and math lessons during the week.  This week I introduced the idea of the 'empty set' or zero.  

So I showed him the little card with nothing on it.  And told him it was an empty set.  Then, I asked him to tell me how many black birds were in the room.  The conversation went a little something like this . . .

Me:  "How many black birds are in the room?"

Andrew:  "Four."

Me:  "What?  No, really, how many black birds are here in this room?  Real ones."

Andrew:  "One."

Me:  "No, Andrew.  There aren't any real black birds in the room.  We're not talking about pretend ones.  You're supposed to say 'none'.  It's an empty set.  Get it?"  

Andrew: "Yes."

Me:  "Say 'yes' if I tell you an empty set and 'no' if it's not an empty set."

Andrew:  "Okay."

Me:  "How many Daddies are in the room?  Is it an empty set?"

Andrew:  "Yes."  - because Daddy was at work.

Me:  "How many tables are in the room?  Is it an empty set?"

Andrew:  "No."  Because there is one table in the room.  (I think he's getting it now.)

Me:  "How many lasagna's are in the room?  Is it an empty set?"

Andrew:  "No."

Me:  "It IS an empty set because there are no lasagna's in the room."  

(not sure if he's getting it after all)

Me:  "Andrew, what is an empty set?"

Andrew:  "Spaghetti?"