Piano Help and a Popcorn World

We can't afford piano lessons for the boys right now, so I borrowed my mom's piano key labels and bought a VERY simple book for the boys to play with. Basically, the book shows big fat black notes with the letter of the corresponding key inside of the note. This book makes playing very easy.
The boys are having a good time.
Calvin has memorized how to play "Silent Night". In fact, he played it for us during FHE this week. While his timing is off, he gets the notes right.
Today we listened to someone sing the song, and Calvin sang along with it . . . this is what I heard from Calvin:
"G, A, G, E.
G, A, G, E.
D, D, B
C, C, G
A, A, C, B, A
G, A, G, E...."

He went through the whole song like that.
Does anyone know music?
Is this a good thing or a bad thing?
How do I work with that?

Help?


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In other conversation with the boys, here is what we talked about over dinner:

Josh: I wish the whole world was made out of popcorn. I wish everything in it was popcorn.
Me: Even chocolate?
Josh: Well, okay, everything but chocolate.
Me: What about pizza? I sure like pizza.
J: Okay, not pizza.....and not water. But everything else.
Me: Ice Cream?
J: umm, okay NOT food. Food is food and Water is water. But everything else is popcorn.
Me: What about our house?
J: Okay, a house is just a house, but everything else....even cars and our road and if we ever got hungry we could just eat a piece of the road . . . or the seats in our car!
Me: So, are you telling me that I wouldn't have a diamond wedding ring? I would have popcorn on my finger?
J: Oh, No! A diamond is a diamond, of course! (That's my boy)
Me: Would it rain popcorn? Would it snow popcorn?
J: (with a gleam in his eye) Yes! We could make popcorn snowmen!
at this time Calvin chimes in...
Calvin: Nope, can't happen because you said that water is water, remember?
J: (looks confused for a sec) Oh, that's right....man!

(And THAT is what we call the water cycle, people)
Poor Josh - and he had such a good idea, too.