Hehehe, those kind of jokes kill me

Here's my last one: the infamous joke of probably. If I want to use the heavy gear, I take out this joke (or John with the red shoes, but you should have the time for that

)
Anyway:
The teacher has just explained the meaning of the word 'probably' and to see if the kids understand it, he asks for some examples.
(George) "OO OO, master, master!"
(Teacher) "Yes, George?"
(George) "Today it's friday and tomorrow it'll probably be saturday."
(Teacher) "Good George."
(Allen) "OO OO, master, master!"
(Teacher) "Yes, Allen?"
(Allen) "Now it's raining, but later, the sun'll probably shine."
(Teacher) "Good Allen."
Then there comes a shy little finger up from one of the last rows. The teacher, glad somebody from there is willing to answer:
(Teacher) "Yes, John?"
(John) "Master, you know I have a sister, don't you?"
(Teacher) "Yes John, but what has that to do with the word 'Probably'?"
(John) "LEMMEFINISHLEMMEFINISH
You know she take pianolessons, don't you?"
(Teacher) "Yes John, but there's still no connection to the word 'Probably'."
(John) "LEMMEFINISHLEMMEFINISH
Well, every saturday, the pianoteacher comes to our house and he and my sister go into the pianoroom, but I am not stupid. No siree! I look through the keyhole. Then my sister takes off her skirt and her panties and the pianoteacher takes off his pants and his underpants and they'll probably go poo in the piano."
Okok, I know. It sounds better when I tell it live, but hey, all jokes do.
-Kon-Tiki-