The song is from season 8 episode 1 of MLP:FiM.
♫ Lyrics for the song:
( You can support the show here: https://itunes.apple.com/us/tv-season/my-little-pony-friendship-is-magic-vol-14/id1355929287 )
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[Choir]
The School of Friendship, first day of class
Will we fail or will we pass?
Students come from far and wide
Brand-new friends here by our side
[Twilight Sparkle]
Take a breath, look around, it's amazing
I can't believe that it's real
Students galore, new ideas to explore
Can't contain the excitement I feel
Can't mess up, can't afford a mistake now
Think "success", keep it firmly in sight
Make sure to do things by the book
Make sure to do it all right
[Choir]
The School of Friendship, must get to class
Will we fail or will we pass?
Students learning from the best
Taking notes to pass the test
[Twilight Sparkle]
Wait, hold on! Not like that! Just a second!
I'm not sure if that method's approved
Let me take a look – yup, right here in the book
[Rainbow Dash]
Come on! We just got in the groove!
[Twilight Sparkle]
Can't mess up, can't afford a mistake now
We are shaping young minds to ignite
Do it like it says in the book
Now make sure you're doing it right
[Pinkie Pie]
There's not an equation on how to have fun
[Fluttershy]
The students look bored now – oh, what have I done?
[Applejack]
Can't teach bein' honest, not sure what to do
[Rarity]
I'm quite certain I'm lost
[Main cast sans Twilight Sparkle]
None of us has a clue!
[Students]
School of Friendship, another class
Wish it were more of a blast
Thought this school would be more fun
Can't wait for our classes to be done
School of Friendship
[Twilight Sparkle]
Can't mess up, can't afford a mistake now
[Pinkie Pie]
No way to have fun
[Fluttershy]
Oh, what have I done?
[Students]
Bored with this class
[Twilight Sparkle]
Think "success", keep it firmly in sight
[Students]
Wish that we could leave our desks
[Rarity]
We don't have a clue
[Students]
Listen to this one request
Make things fun, we're really stressed
[Twilight Sparkle]
Make sure to do things by the book now
[All sans Twilight Sparkle]
Can we tell her this thing is a mess?
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"My Little Pony" is owned by Hasbro,
"MLP: Friendship is Magic" is created by Lauren Faust.